United Nations Peacekeeping for Ukraine Under Scrutiny

Any Ukraine ceasefire will likely require a follow-on peacekeeping effort, at a time when the United Nations is looking to reform Peacekeeping Operations (PKO). On 24 March 2025, the United Nations Security Council (UNSC) held its 9884th meeting to discuss the future of PKOs and inform a ‘Peacekeeping Ministerial’ to be held in Berlin in March this year. The possibility of a Ukraine ceasefire, the challenge of expanding mandates and the complexity of multi-dimensional PKOs elsewhere makes this a timely and pertinent debate for the UNSC.

UN peacekeeping’s principles are: consent of the main parties, impartiality, non-use of force except in self-defence and defence of the mandate, with some referring to a fourth principle of and maintaining peace and security. These afford credibility and a degree of political protection to the PKO vital to ensure operational and logistical success. Self-defence is legally an inherent right, so it is the mandate that determines where and how else force can be used. Insufficient or inappropriate permissions and poorly exercised rules of engagement have on occasion caused significant issues.

Peacekeeper Records

Infamously, UN Peacekeeper inaction due to mandate restrictions, failed to prevent elements of the Rwandan genocide in 1994. More recently, many in Mali saw the lack of direct confrontation with terrorists by MINUSMA (the UN PKO mission) as a failure. This perception and accusations from the Malian junta that the UN was not impartial and was fuelling community tensions (possibly encouraged by Russia) ultimately resulted in the withdrawal of host nation consent. MINUSMA finally closed down in 2024. MINUSCO, the PKO in the Democratic Republic of Congo, also lost host nation consent and was due to draw down. However, this mission had a stay of execution following the recent rapid deterioration of the security situation, and under their primary mandate aim it continues to provide protection to civilians. To say that these missions have failed is an oversimplistic assessment, but they exemplify why a reassessment of PKOs is overdue.

Given discussion of a possible ceasefire in Ukraine, it is important to consider peacekeeping in this context. Is Ukraine a prime candidate for a UN PKO? After all, the vision for peacekeepers was as a buffer between combatants. UNIFIL formed to monitor Israeli withdrawal from Lebanon and ensure humanitarian access, and UNFICYP, the mission to prevent further fighting between Greek and Cypriot communities in Cyprus, continue this tradition. Whilst Russia’s suggestion that the UN take control of Ukraine to elect a ‘competent’ government was more propaganda than genuine proposal, some have considered a role for the UN in a post-conflict Ukraine. Indeed the Russian permanent representative to the UN noted that any force without a UN mandate would be a legitimate target, potentially making a case for a UN PKO.

However, there is a lack of trust, with NATO and the EU assuming that following a ceasefire, Russia will retain some of its 2022 aspirations regarding Ukraine. Current talk is around a ‘Reassurance Force’, made up from a coalition of the willing, a proposal opposed by Russia. This force would need to be sufficiently robust and technologically competent as to provide deterrence against further Russian aggression. A UN PKO with sufficient capacity (and will) to deter aggression from a military as large as Russia’s, is just not viable for multiple practical and resourcing reasons. Furthermore, the principle of presence with consent would cause further issues were Russia to remove consent and cease to recognise the legitimacy of any UN PKO.

Nonetheless there could be some roles for the UN following any ceasefire. Impartial UN contributions could include ceasefire monitoring and hosting of continuing peace talks and implementation management. The UN’s expertise and experience, could, for example, be useful in impartially investigating any allegation of ceasefire breach including by non-state actors.

PKO's into the Future

Despite the limitations and challenges outlined above, PKOs remain a core element of the UNs vision. The UN General Assembly’s ‘Pact for the Future’ agreed to ‘adapt peace operations to better respond to existing challenges and new realities’. The UNSC, in taking this forward, was briefed on and then discussed these challenges and potential modalities for improvement.

The UNSC heard that multiple studies have demonstrated that PKOs have been successful in many of their aims, particularly in protection of civilians. Whilst achievements are often evident on the ground, quantifying them can be difficult. Proving causal links and second order benefits of UN presence is challenging and evidencing counterfactual arguments is equally problematic. It is difficult to meaningfully answer questions such as, ‘would the situation have been worse, and how much worse, in the absence of the UN?’ However, even where successes are realised, it was noted that there can still be a ‘dissonance between these finding as the lived experiences of this in conflict setting’. This is especially true where there is a confused and/or unrealistic expectation of the role of the PKO.

Understanding and assessing PKOs can be complicated by intricate mandates, particularly those that grow year-on-year without increased resourcing. Mandate creep risks distraction through reprioritisation of existing tasks, ineffective resource allocation and shifting goalposts. Cognisant of these challenges, a number of suggestions were made to the UNSC. These included a stronger planning culture in the secretariat, that better discerns emerging trends with a willingness to respond proactively; a greater tolerance or risk and acceptance that initiatives should be ‘allowed to fail’; and that the Secretariat should not ‘self-censor’ its advice based on political expectation but present the fullest range of options to the Council. Essentially advocating for better planned, more focused and, potentially, bolder missions.

Additionally, a modular approach to PKO was proposed. A UN commissioned report identifies thirty possible modules, with associated resources and objectives, ranging from ‘Preventative Deployments’, through ‘Police Assistance’ to ‘Maritime Security’. Naturally, ‘Atrocity Prevention’, ‘Protection of Civilians’ and ‘Ceasefire Monitoring’ are amongst the primary modules.

Although reforms are yet to be agreed, there was broad support for the above approach, including from the US and China; the two largest funders of PKO. Amongst numerous national recommendations, China cautioned that ‘regardless of how mandates are adapted, they must remain focused on their core goals’ and countenanced against every mandate renewal leading to its expansion and called for continued efforts for ‘efficient use of resources’. This reflects a wider concern with the cost of UN PKO and the financial constraints faced by the UN.

The Bottom-Line

In keeping with the US zeitgeist, their representative emphasised a need for greater accountability and value for money. There was no suggestion that the US would renege on its funding commitment. However, their opinions will matter given that the US is the largest direct funder of PKOs and the largest provider of ‘pre-deployment’ training for troop contributing countries (TCC), a line of funding which is effectively discretionary. The ineffectiveness of some TCCs is a recognised issue. However, an overly prescriptive and quantitative approach to ‘measures of effect’ (MoE) should be approached with caution. Many UN outputs are difficult to quantify, coming through effects like attitudinal changes and deterrence by denial (by presence and surveillance); these are difficult to capture as MoEs. Metrics based, for example, on patrols data may have utility in holding TCCs to account, but risk missing key PKO benefits.

The one dissenting voice on the proposed approach was that of Russia. Their observations included rebuffing claims that ‘the geopolitical context is hindering efforts or that misinformation is to blame for everything’ and stating that a ‘formalistic search for so-called 'innovative” solutions …, which are often artificial innovations, seems ill-advised’. It is not clear whether its objections are informed by having benefitted from the withdrawal of MINUSMA from Mali or having been implicated in disinformation campaigns with respect to MOUNSCO in DRC.

Innovative solutions are required. One line of effort is working with other institutions able to deploy peace support forces, noting that the UNSC has not mandated a new PKO in 10 years. The African Union and sub-regional groupings are able to mobilise with more aggressive rules of engagement and at faster pace than the UN. They have collectively mobilised 38 missions in 25 years. With multiple African-led mediation efforts currently ongoing in response to conflicts in the region, this exemplifies the maxim of ‘African solutions to African problems.’

However, much of this serves to underline that the UN has a role to support these activities, and an opportunity to reform UN PKOs that will be balanced to ensure both effectiveness and efficiency. Tailoring the combination of UN missions with other actors: UN funding for non-UN missions (for example, through resolution 2719 that allows for hybrid UN supported funding for AU led operations); improving logistical support for non UN missions; or simply having UN endorsement (often post hoc) for African led peace missions are all worthy of further discussion.

Setting Expectations

The reasons for missions not fulfilling mandates can be myriad and complicated. A lack of genuine commitment, obfuscation and non-adherence to agreements, deterioration of the security situation due to third party actors (e.g. terrorists), corruption and unrealistic expectations are but some. The UN Secretary General also highlighted that ‘organized crime, the weaponization of new technologies and the effects of climate change are all testing our capacities to respond’. Many complicating factors will remain outside of the UN’s control, but PKO design should be sufficiently flexible and innovative to mitigate these challenges. It must do so in a context of growing financial constraints paying particular attention to the design of mandates, resourcing, reporting and measures of success. These are the aspects that are rightly under scrutiny as the UN attempts to rehabilitate a damaged reputation.

It must be acknowledged that focus on PKOs with all the other current global security threats and distractions is difficult. Reforms made now have the potential to recalibrate UN support to peace and security for years to come; failure to address the issue adequately risks seeing further disillusionment and operational impotence. Irrespective of the modalities chosen, the need for adequate training and resourcing will remain key. Perhaps more fundamental, in an age of strategic communications, is to ensure the aims and outcomes of PKOs are clearly defined and unambiguously communicated to local populations, host governments, the UN and the world at large.

© RUSI, 2025.

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