The British military will send some 8,000 troops to Europe as part of a larger allied deployment to deter further Russian aggression, British officials said.

The British troops will be serving in the Joint Expeditionary Force, a British-led multinational group created in 2014 in response to Russia’s seizure of Crimea from Ukraine.

Tens of thousands of troops from Joint Expeditionary Force and NATO countries will participate in exercises between April and June, Britain’s defense ministry said in a statement released on Friday. The deployment was reported earlier by The Guardian.

“These exercises will see our troops join forces with allies and partners across NATO and the Joint Expeditionary Force in a show of solidarity and strength in one of the largest shared deployments since the Cold War,” Ben Wallace, the British defense secretary, said in the statement.

The exercise was long planned, and Britain’s participation had been announced in February, but British officials said it had been expanded as a result of Russia’s invasion of Ukraine.

The joint force’s deployment is temporary, but NATO allies are considering whether to expand the forces they deploy on a rotational basis to Poland and the Baltic countries of Estonia, Latvia and Lithuania. Those discussions are expected to continue at the NATO summit in Spain, scheduled to begin June 29.

Those NATO battle groups have roughly 1,500 soldiers each. Some NATO allies want to expand those forces to brigade size, which could make them around 3,000 troops each.

NATO has also been discussing ways to offer enhanced security support to Sweden and Finland should they seek membership in the alliance. While NATO is expected to offer membership quickly, it will take months for individual allies to ratify the agreement, leaving those countries without the alliance’s security guarantees.

The joint-force deployment will focus in part on the security of the Baltic region, and it could offer a measure of reassurance to Finland and Sweden. Both participate in the force.