The UK is to step up its presence in countries which border Russia, as part of a new plan to be a "dynamic, agile, cutting-edge global power".
Boris Johnson and Sir Michael Fallon announced the project as they launched the joint international defence engagement strategy ahead of the annual Munich Security Conference.
It includes a "stepping up" of global commitments and leadership in organisations such as Nato and the United Nations and a shift towards a defence policy which is more "international by design".
Among other measures, the strategy includes more Nato military exercises with allies such as Ukraine, Poland and Estonia, which are faced with increasing Russian aggression.
It comes after the 2015 Strategic Defence and Security Review made defence engagement a core task for the first time.
Defence Secretary Sir Michael said: "Our increased ambition for defence engagement abroad demonstrates the UK's global role.
"Whether it's by increasing our military expertise in the Middle East, training Nigerian forces in maritime security, or RAF Typhoons exercising over South Korea, Britain is committed to working internationally to protect our people and interests."
Foreign Secretary Mr Johnson said: "The International Defence Engagement Strategy ensures we get the best value from our brilliant and brave Armed Forces and world-class Diplomatic Service, enabling them to deliver security and prosperity for the British people.
"This is about sending a clear signal of the UK's intent as a dynamic, agile, cutting-edge global power."
Press Association
