NATO is to begin its biggest war games in decades next week, with around 90,000 military personnel taking part in months of drills aimed at showing that the alliance can defend all of its territory up to its border with Russia, top officers said on Thursday.

The exercises come as an increasing number of analysts say that Russia has largely already defeated the military alliance in its proxy war in Ukraine.

In the months before President Vladimir Putin ordered Russian troops into Ukraine in February 2022, Nato began reinforcing security on its eastern flank, in the alliance’s biggest build-up of forces since the cold war.

The war games are meant to deter Russia from targeting a member country.

Nato says that Steadfast Defender 24 will demonstrate that the military alliance “can conduct and sustain complex multidomain operations over several months, across thousands of miles, from the high north to central and eastern Europe, and in any condition.”

Troops will be moving to and through Europe until the end of May in what the 31-nation alliance describes as “a simulated emerging conflict scenario with a near-peer adversary.”

Under Nato’s new defence plans, its chief adversaries are Russia and terrorist organisations.

Nato’s supreme allied commander, US General Christopher Cavoli, told reporters: “The alliance will demonstrate its ability to reinforce the Euro-Atlantic area via transatlantic movement of forces from North America.

Gen Cavoli said it would demonstrate “our unity, our strength and our determination to protect each other.”

Admiral Rob Bauer, who chairs Nato’s military committee, said that the war games involve “a record number of troops that we can bring to bear and have an exercise within that size, across the alliance, across the ocean from the United States to Europe.”

Adm Bauer described this as “a big change” from the number of military personnel taking part in exercises just a year ago.