Nato is considering abandoning its recent practice of holding annual summits, six sources have told Reuters, in a development that further undermines the crumbling trust in the military alliance that has been the bedrock of European security for decades.

The discussions, confirmed by a senior European official and five diplomats from Nato member countries speaking on condition of anonymity, reflect growing anxiety within the alliance that the US would not come to a European power’s military aid under the Article 5 collective security clause if it were attacked by Russia or another adversary.

And that fear has been growing. The German intelligence services have issued two reports saying that Russia may attack Europe after five years. But Polish Prime Minister Donald Tusk claimed that Russia could be ready to launch an offensive within a matter of months and that Europe’s Eastern flank is largely undefended.

Tensions on the Eastern border have risen recently, after Ukraine flew long distant drones over the Baltic state territory to reach Russian oil export terminals in the sea in a sustained attack that has dented Russia’s oil exports. That earned the EU a sharp rebuke and a veiled threat that Russia might retaliate and shoot down the drones flying in Nato airspace.

The Nato summits have been a key platform to demonstrate the members solidarity in supporting Ukraine and defying a Russian military threat. However, the mood at the summits has deteriorated sharply since Trump took over. At the last Nato summit in the Hague, the Trump administration used the event to demand European members increase their spending on defence dramatically to 5% of GDP by 2032.

One diplomat said the 2027 summit, to be held in Albania, would likely take place that autumn and Nato was considering not holding one at all in 2028. Another said some countries were pushing to hold summits every two years, adding that no decision had been taken and Secretary General Mark Rutte would have the final say.

The alliance's next scheduled summit takes place in Ankara, Turkey, on July 7 and 8. That gathering already looks set to be even more awkward than the last meeting in the Hague.

In response to a query from Reuters, a Nato official said: "Nato will continue to hold regular meetings of Heads of State and Government, and between summits Nato Allies will continue to consult, plan and take decisions about our shared security."

In a sign of how far trust in the alliance has fallen, Europe has stepped up preparation to build a Euro Nato based on the EU treaty’s Article 42/7, its own collective security agreement amongst EU members that does not include the US.

A history of difficult encounters

Nato leaders have met every summer since 2021, but the frequency of the summits has varied over the alliance's 77-year history, with only eight summits held during the entire Cold War period.

Trump has put the cat amongst the pigeons since he took over as he has classed Europe as “freeloaders” piggy backing on the heavy US investments into defence, but never meeting their own obligations to spend at least 2% of GDP on their own defence. Trump's first three Nato summits during his initial term were "contentious events, dominated by his complaints about low allied defence spending."

Former Nato Secretary General Jens Stoltenberg, who managed those encounters at close quarters said at the 2018 summit, Trump threatened to walk out in protest at other allies' defence spending. "Had he made good on his threat to leave in protest, we would have been left to pick up the pieces of a shattered Nato," Stoltenberg wrote. Last year's summit in The Hague set a new benchmark for minimised expectations.

This year's Ankara summit looks likely to be considerably more fraught. Trump launched US military operations against Iran without consulting or informing Nato allies. He then called on European Nato support to reopen the Strait of Hormuz and was flatly refused by all of Europe. When allies declined, he openly threatened to pull the US out of Nato on two separate occasions. He has also repeatedly suggested that the US would only honour Nato's mutual defence guarantee on a tractional basis, if the victim had spent enough on defence.

In the months before the Iran conflict, he had also laid claim to Greenland, an autonomous territory belonging to fellow Nato member Denmark — itself a direct challenge to the territorial integrity of a member state.

Two of the sources mentioned Trump as a factor in the summit frequency discussions, but several said broader considerations were also at play.

During the Cold War, when the threat of Soviet aggression was arguably more existential than anything Nato faces today, heads of state gathered only eight times over four decades. The annual summit format is a relatively recent innovation, accelerated by the post-2022 urgency of Ukraine and the perceived need to demonstrate allied solidarity through visible leader-level engagement.

Critics of the current rhythm note that summits have increasingly become diplomatic performance events rather than decision-making forums, with the real alliance business — force commitments, capability targets, operational planning — conducted at the level of defence ministers, military chiefs and ambassadors in the North Atlantic Council. The pressure to produce a summit communiqué that all thirty-two members can agree to has, in some analyses, produced documents that are lowest-common-denominator in substance and highest-possible-drama in presentation.