By Sabine Siebold and Polina Nikolskaya

BERLIN/LONDON, May 26 (Reuters) – NATO will strengthen the defence of its eastern flank with a new structure that would facilitate the rapid deployment of forces in Latvia and Estonia in the event of a war with Russia, two sources familiar with the matter told Reuters.

At present, NATO forces in all three Baltic nations as well as northern Poland come under the command of a single multinational headquarters in the Polish city of Szczecin. The planned change underlines the strategic importance of the Baltics, which have been in focus since Russia’s invasion of Ukraine.

Assigning a second corps for the region will allow NATO to bring in “mass at speed”, as one military official described it, addressing the region’s limited strategic depth and vulnerability. 

When fully operational, an army corps typically commands three divisions, or 40,000 to 60,000 troops. In peacetime, it normally exists as a skeleton command structure, with specialist functions such as artillery, air defence and medics in place to allow rapid deployment of troops when needed.

Germany and the Netherlands, in coordination with NATO, have reached agreement to assign the German-Netherlands Corps, based in the German city of Muenster, to the defence of Latvia and Estonia, the military sources told Reuters on Tuesday.

European allies are assuming more responsibility for their own security, amid fierce criticism from U.S. President Donald Trump who most recently accused European NATO members of a lack of support in the Iran war and announced Washington would withdraw 5,000 U.S. troops from Germany. 

The deal cleared the last hurdle, which consisted of a lack of corps troops, the sources said, alluding to the critical capacity any corps needs in areas such as long-range artillery, air defence, as well as engineers and medics. 

Together with other partners, Germany and the Netherlands will now build up these forces, the sources said.     

It was not immediately clear when the decision would take effect and how many troops would fall under the command of the new headquarters unit in any conflict.

The Dutch defence ministry said assignment of the corps was “currently being further elaborated” and declined to give details. The German defence ministry declined to comment, citing ongoing coordination efforts with NATO.

NATO said it would respond later.

NATO officials have warned for years of an increased threat from Russia, which they say could potentially mount a large-scale assault on allied territory as early as 2029. Moscow denies aggressive intentions and accuses the alliance of stoking tensions by expanding into neighbouring territory.

(Reporting by Sabine Siebold in Berlin, Polina Nikolskaya in London and Anthony Deutsch in AmsterdamEditing by Keith Weir)