The British Prime Minister, Tony Blair, has said it is impossible to fight terrorism without the co-operation of Russia.
He was speaking at a news conference at the end of a summit between EU leaders and the Russian President, Vladimir Putin, in London.
The two sides also discussed economic growth and energy supplies as the EU now depends on Russia for one third of its oil supplies.
Asked if Europe would now feel constrained in making any criticisms of Moscow because of such dependence, Mr Blair said there was strong mutual interest.
