United Nations diplomats are quietly preparing for the possibility that the organisation may be unable to agree on its next secretary general, a scenario that could leave the post temporarily vacant when António Guterres’s term ends in December. According to reporting by Observer UK, growing rivalry among the world’s major powers has cast doubt on whether consensus can be reached at a moment when the UN is under exceptional strain.
The secretary general is selected by the UN security council, where the five permanent members — the United States, China, Russia, France and the UK — must all agree. That requirement is now emerging as a critical obstacle. The search for a new leader is unfolding against a backdrop of intensifying global conflict, institutional fragility and a retreat from multilateralism led by Washington, the UN’s largest financial contributor.
The challenges facing the organisation are stark. The White House recently announced its withdrawal from 66 international bodies, around half of them linked to the UN system, while an estimated 60 wars are currently raging worldwide, the highest number since the second world war. UN peacekeeping missions are under scrutiny, budgets are shrinking, and confidence in the multilateral order the organisation was created to uphold is eroding.
Richard Gowan of the International Crisis Group described the UN’s predicament as a prolonged decline, arguing that its next leader will be forced to oversee painful cuts and mergers while persuading both major and smaller powers that the institution still has relevance. The difficulty, diplomats say, is finding a candidate capable of commanding respect across a deeply divided security council without being vetoed by any of its most powerful members.
The formal nomination process is due to begin soon, with governments submitting letters backing potential candidates. Tradition and a 1997 UN resolution had fueled expectations that the next secretary general might be a woman from Latin America, a region that has never held the post. That assumption has been shaken by the return of Donald Trump to the US presidency. His administration’s hostility toward gender and diversity initiatives is widely seen as weakening the prospects of figures such as Michelle Bachelet, the former Chilean president and ex-UN high commissioner for human rights.
Several candidates are already positioning themselves. Rafael Grossi of Argentina, the head of the International Atomic Energy Agency, has been campaigning actively, leveraging his role overseeing inspections of Iran’s nuclear programme and monitoring safety at Ukraine’s Russian-occupied Zaporizhzhia nuclear plant. Other names in circulation include Rebeca Gryspan of Costa Rica, who helped broker the Black Sea grain deal, and Alicia Bárcena, Mexico’s environment secretary and a respected scientist. Each faces the same dilemma: how to appeal to rival powers while maintaining credibility with the wider UN membership.
Jane Kinninmont of the UN Association UK summed up the challenge bluntly, asking how any candidate can avoid vetoes from leaders such as Vladimir Putin, Donald Trump or Xi Jinping while still representing a world increasingly skeptical of unchecked superpower power.
If agreement proves impossible, diplomats say there are limited fallback options. Guterres could be asked to remain temporarily, or his deputy could assume the role on an interim basis. The greater risk, analysts warn, is that a compromise choice might lack the authority or vision needed at such a critical juncture. A bland bureaucratic caretaker, Gowan cautioned, could accelerate the UN’s slide into political marginality rather than arrest it.
The leadership uncertainty comes amid widening geopolitical rifts. The Trump administration’s push to dominate the western hemisphere has unsettled Europe, tensions over Ukraine continue to pit Russia against western powers, and China is increasingly viewed as a systemic rival by both Washington and Brussels. In this fractured environment, some experts argue that a divided security council does not necessarily render the UN obsolete.
Thant Myint-U, author of Peacemaker and grandson of former UN secretary general U Thant, noted that the organisation has historically been most valuable during periods of intense rivalry, including the cold war. He argued that the next secretary general must refocus the UN on its core mission of preventing war between states and be willing to intervene decisively in major conflicts to demonstrate the organisation’s continuing relevance.
As Observer UK reports, the next secretary general will begin a five-year term in January 2027, with the option of one renewal. Whether that term starts with a strong mandate or an improvised stopgap may determine not only the future of the UN’s leadership, but also the credibility of multilateral diplomacy in an increasingly unstable world.
