BRUSSELS (AFP) - EU foreign policy chief Catherine Ashton said she would hold talks in Madrid on Tuesday with Russia's Foreign Minister Sergei Lavrov, as the bloc announced an emergency summit on the crisis.

"Extraordinary summit of EU presidents and prime ministers called for Thursday to help de-escalate situation in Ukraine," EU President Herman Van Rompuy wrote on Twitter, after EU foreign ministers warned Russia that ties could suffer if it does not change course after its military intervention in Crimea.

Ashton said after chairing the Ukraine crisis talks gathering the EU's 28 foreign ministers that she would travel on to Kiev on Wednesday.