The EU needs a long-term strategy on Russia instead of simply reacting to events, the new EU summit chairman Donald Tusk has said, reports GHN based on BBC.
Mr Tusk said he had been "really moved" by the leaders' discussion of the Ukraine crisis.
Earlier, the EU tightened sanctions against Russia over its support for armed separatists in eastern Ukraine.
"We need a plan for years... we're not too optimistic, we have to be realistic," Mr Tusk said.
"Russia is our strategic problem, not Ukraine," said Mr Tusk, the former Polish Prime Minister. "The biggest challenge is Russia's approach not only to Ukraine but also to Europe.
"Our discussion [on Ukraine at dinner] showed Europe united as never before. Russia's behaviour needs a pragmatic solution, a united, common position."
Poland, bordering on Ukraine, has long had tense relations with Russia, and is among the most vocal critics of Russian President Vladimir Putin.
Pro-Russian rebels in eastern Ukraine still have heavy weapons including tanks and rockets, despite demands by Ukraine and the West for them to disarm. Continuing clashes in the Donetsk region have undermined peace efforts.
Under the latest measures against Russia, all EU tour operators will be barred from operating in Crimea and European investment there will be banned. Russia annexed Crimea in March.
Italy's Prime Minister Matteo Renzi said "we must work with Russia to push it out of Ukraine".
