Britain will send hundreds more troops close to Russia’s border, the Government has said, as the Prime Minister also called for “pressure” on Moscow over the Syria crisis.

Around 800 soldiers along with tanks, armoured vehicles and drones will now head to Estonia in the spring in a Nato effort to reassure the Baltic states over Russian aggression.

The boosted mission, up from 500 announced earlier this year, will be Britain’s largest long-term deployment to one of Russia’s neighbours since the end of the Cold War.