Brussels, Mar 23 (IANS): The EU has recalled its ambassador from Moscow after leaders on the continent sided with Britain over the poisoning of a former Russian double agent in the UK, saying it was "highly likely" Moscow was responsible for the attack.

Following a summit in Brussels on Thursday to discuss the response to the Salisbury nerve agent attack, the European Council of EU leaders agreed "there was no plausible alternative explanation", the BBC reported.

"We stand in unqualified solidarity with the UK in the face of this grave challenge to our shared security," the statement by the European Council said.

British leader Theresa May said the Salisbury poisoning was "part of a pattern of Russian aggression against Europe".

Moscow denies responsibility for the attack on ex-spy Sergei Skripal and his daughter Yulia. They remain in a critical but stable condition after the attack on March 4.

The EU said its ambassador to Russia was recalled "for consultations". European Council's President Donald Tusk tweeted that all leaders agreed Russia's responsibility for the attack was highly likely.

France, Poland, Estonia, Latvia and Lithuania were reportedly considering expelling Russian diplomats as requested by the UK government, in a coordinated strike against Moscow, according to a Guardian report.

Lithuanian President Dalia Grybauskaite said: "All of us, we are considering such measures." She added that she had not congratulated Putin on his re-election.

On Thursday night, Dutch Prime Minister Mark Rutte said the EU ambassador to Russia was being recalled to consult with Brussels over the Salisbury attack. Rutte characterised this as a "measure" rather than a formal "sanction" against Moscow.

Britain had expelled 23 Russian diplomats in retaliation for the nerve agent attack. In the run-up to Thursday's summit, British officials shared intelligence with their EU counterparts about the issue.

Theresa May also met German Chancellor Angela Merkel and French President Emmanuel Macron in Brussels and a spokesperson of Downing 10 claimed that "the UK, Germany and France reaffirmed that there is no plausible explanation other than that the Russian state was responsible".

The three leaders agreed on "the importance of sending a strong European message in response to Russia's actions and agreed to remain in close contact in coming days," a spokesperson was quoted as saying.