After nine years as secretary-general of the world's most powerful military alliance, Jens Stoltenberg was expected to end his tenure as NATO chief in late September. But with no clear consensus on a successor, experts say the 64-year-old — who has already extended his term twice — will likely be asked to stay on until at least next April.

“While it is not publicly known whether a final decision has been made, everything now suggests that Stoltenberg’s mandate will be extended beyond his current term at the upcoming NATO summit in Vilnius, Lithuania, from July 11 to 12,” said Paal Sigurd Hilde, a NATO expert at the Norwegian Institute for Defense Studies.

Most likely, the extension will be either until April 2024, when the the alliance marks its 75th anniversary, or until the summer, when the next NATO summit is likely to be held.

The NATO secretary-general is usually appointed by consensus among the alliance’s 31 member states, and normally for a four-year term.

“The ambassadors serving on the North Atlantic Council — NATO’s top political decision-making body — meet regularly and very confidentially to present their national candidates and gauge the degree of support from other allies until consensus is reached on one candidate,” said Jamie Shea, a former deputy assistant secretary-general for emergency security challenges at NATO.

At the end of his or her term, the incumbent might be offered the opportunity to stay on.

NATO Secretary-General Jens Stoltenberg (center) attends a news conference with some NATO country leader at The Hague on Tuesday. | AFP-JIJI
NATO Secretary-General Jens Stoltenberg (center) attends a news conference with some NATO country leader at The Hague on Tuesday. | AFP-JIJI

The position has traditionally been held by a European political figure, while NATO's chief military officer, the Supreme Allied Commander Europe, has always been from the U.S.

In recent months, several names have surfaced as potential successors to Stoltenberg. These names have included Danish Prime Minister Mette Frederiksen, who recently said in Washington that she is not vying for NATO's top job, Estonian leader Kaja Kallas, and British Defence Secretary Ben Wallace, a former soldier who has made clear that he would like the job but has played down his chances.

However, no consensus has been reached. That said, if Stoltenberg were to agree to stay on for up to a year, there would be plenty of time for others to toss their hats into the ring.

At the same time, promoting gender equality has been important to NATO as an international organization, so there has been increased talk of selecting a female secretary-general.

“It is a widely held view that it is high time to have a woman in NATO’s top civilian position,” said Shea, who is now professor of strategy and security at the University of Exeter.

Such a move would allow NATO to present a more modern face and connect with different audiences and younger generations, he added.

Danish Prime Minister Mette Frederiksen delivers a speech in Allinge, Denmark, on June 16. | Ritzau Scanpix / Ida Marie Odgaard / via REUTERS
Danish Prime Minister Mette Frederiksen delivers a speech in Allinge, Denmark, on June 16. | Ritzau Scanpix / Ida Marie Odgaard / via REUTERS

Several female candidates have emerged this time, so choosing a woman should be “inherently easier,” he said, while noting that “choosing the best and most politically acceptable candidate will come first.”

There is similar pressure to look eastward, with the grip of Western Europeans on the post persisting even after the Cold War ended and former Warsaw Pact nations were welcomed into the alliance.

“Russia’s war on Ukraine has rightly focused attention on how NATO can bolster defense and deterrence on its eastern flank,” said James Black, assistant director of defense at RAND Europe, part of the nonprofit RAND Corp. “Countries such as Poland or the Baltic States have long been talking about the threat from Russia and are now making an outsized contribution to supporting Ukraine. Some will be asking if it’s time that this shift eastward be reflected in NATO’s leadership appointments.”

Experts, however, emphasize that the lack of consensus on a successor is not the only reason why Stoltenberg — a former Norwegian prime minister — will be asked to continue as NATO chief for the next few months.

There is also a reluctance to change the secretary-general at a time when the trans-Atlantic alliance is facing crucial challenges such as providing substantial military support to Ukraine and finding consensus on defense plans and spending levels — not to mention Turkey and Hungary’s apparent reluctance reticence to ratify Sweden’s membership in the alliance.

“There is a tendency to avoid change of key positions during a period of crisis if the office holder is seen as dependable, capable and acceptable,” said Garren Mulloy, an international relations professor at Daito Bunka University in Tokyo.

“Stoltenberg is seen as these things, but the question is whether he is willing to extend,” he added.

British Defense Secretary Ben Wallace meets the crew of an Ajax Ares armored personnel carrier, to view Ukrainian soldiers training on Challenger 2 tanks, during a visit to Bovington Camp, a British military base in Dorset, England, in February. | Pool / via REUTERS
British Defense Secretary Ben Wallace meets the crew of an Ajax Ares armored personnel carrier, to view Ukrainian soldiers training on Challenger 2 tanks, during a visit to Bovington Camp, a British military base in Dorset, England, in February. | Pool / via REUTERS

But how much can a NATO secretary-general really do?

It’s worth noting that the position does not come with a military command and that political and military strategic decisions rest with NATO member states. Indeed, as Hilde put it, the position of NATO secretary-general is often said to be more that of a “secretary” than a “general.”

But while the position may not hold much formal power, it comes with a great deal of influence and authority among the allies.

The secretary-general chairs NATO summits and ministerial meetings, sets the consultation agenda and leads the alliance in terms of ideas and policy proposals.

This influence has been evident in Stoltenberg’s leadership on defense spending targets, assistance to Ukraine and NATO’s new Strategic Concept document, Shea said. The secretary-general is also responsible for keeping the alliance together and negotiating compromises as well as being the public face of NATO. It is thus a position of enormous international prestige, which is why so many countries wish to compete to have their candidates fill it.

Experts say Stoltenberg has performed well when handling difficult leaders such as former U.S. President Donald Trump or current Turkish President Recep Tayyip Erdogan, both of whom have found their relations with other NATO leaders to be tense and even confrontational at times.

Estonian Prime Minister Kaja Kallas and Ukrainian President Volodymyr Zelenskyy attend a joint news briefing in April. | Ukrainian Presidential Press Service / via REUTERS
Estonian Prime Minister Kaja Kallas and Ukrainian President Volodymyr Zelenskyy attend a joint news briefing in April. | Ukrainian Presidential Press Service / via REUTERS

The former Norwegian prime minister has also played a key role in deepening institutional cooperation between NATO and the European Union — something that was once a source of constant friction despite the two bodies’ overlapping memberships, said Black.

That said, Stoltenberg’s accomplishments go beyond boosting unity in the Euro-Atlantic community and rallying support for Ukraine. Under his watch, NATO has also begun to look further afield.

Arguing that the security of Europe is inseparable from that of the Indo-Pacific, he has also played a key role in increasing NATO’s engagement with Japan, South Korea, Australia and New Zealand, which are informally known as the “Asia-Pacific Four” (AP4) and are expected to enter deeper partnerships with the alliance later this year.

NATO has also been stepping up its investment in innovative new technologies, such as artificial intelligence and quantum computing, while also boosting its role in space.

“NATO allies look to these Asia-Pacific partners both to learn about their experiences in relations with China and cooperate in what NATO calls emerging and disruptive technologies, particularly with Japan and South Korea,” said Hilde.

Though the timing may not yet be agreed upon, what is clear is that NATO’s next leader will face a world of conflict and flux — rocked by war in Europe, growing tensions in the Indo-Pacific and mounting pressures from climate change, economic disruption and new technologies, observers say.

“Picking the right candidate to steer the alliance through these interweaving challenges is not only important for NATO; it matters for the wider peace and stability of the whole globe,” said Black.