Brussels - The EU has announced plans to spend nearly 20 billion euros on defence over its next long-term budget, as the bloc seeks to boost its resilience to the perceived threat from Russia.

After decades of failed attempts, EU members signed a defence cooperation agreement in December, spurred to action by Russia's annexation of Crimea in 2014 and claims of state-sponsored cyberattacks.

The European Commission, the bloc's executive arm, on May 2 launched plans to give the pact financial clout out of its 1.279 trillion euro budget for 2021-2027, allocating 19.5 billion euros to defence over the seven-year period.

The sum includes 6.5 billion euros for "military mobility", an ambitious project to make it easier to move troops and equipment around the continent that NATO commanders say is essential to present a credible deterrent to would-be aggressors.

But the bulk of the money -- 13 billion euros -- will go to the European Defence Fund, unveiled last June as part of French-German efforts to give the bloc fresh impetus in the wake of Brexit.

The fund will get 4.1 billion euros for defence research, focusing on emerging and future security threats -- for example work on robotics and drones.

A further 8.9 billion euros will be to help EU countries cooperating to produce big-ticket hardware items such as tanks and helicopters.

Only three EU members refused to sign up for the defence cooperation agreement -- Denmark and Malta, plus Britain, which is leaving the bloc next year.

Brussels has been at pains to insist first that greater defence cooperation will not lead to an "EU army" and second that the project will complement NATO, rather than competing with it.

There have also been fears since the election of President Donald Trump that the US would not honour its longstanding commitment to come to Europe's aid in a military crisis, and European Commission chief Jean-Claude Juncker has said the bloc "cannot and should not outsource our security and defence".