Germany, Poland and Sweden expelled three Russian diplomats in a coordinated retaliation on Monday for the expulsion of three European Union diplomats by Russia while the EU's foreign policy chief was visiting Moscow last week.
The EU executive defended Josep Borrell over his trip to Russia where has said he had learned of the expulsions via social media while speaking with Russian Foreign Minister Sergei Lavrov in Moscow on Friday.
Kremlin spokesman Dmitry Peskov said on Monday the removal of diplomats from Germany, Poland and Sweden, accused by Moscow of taking part in protests last month against jailed Kremlin critic Alexei Navalny, took place a day before Borrell's trip.
In a blog released late on Sunday, Borell said his pleas to Russia to halt the expulsions were ignored. Estonia's former defence chief Riho Terras, now an EU lawmaker, has started a campaign to call for Borrell's resignation.
But the executive European Commission said it had no regrets about Borrell making his first trip to Moscow as the coordinator of EU foreign policy because Russia was on a course towards confrontation - which Borell sought to avert.
"The trip was necessary. One doesn't give up on a trip because it looks difficult," Commission spokesman Eric Mamer said in Brussels. "A trip is not a success or a failure on the basis of what happens during a particular moment."
Belgium also issued a statement in support of Borrell.
Peskov told reporters that Russian officials "were not the initiators of the collapse in relations".