British Prime Minister David Cameron announced on Wednesday he will fly to the Russian resort of Sochi on Friday to discuss the Syrian conflict with President Vladimir Putin.
The trip was confirmed by the Kremlin, which said in a statement that Cameron would be on a "working visit" without giving further details.
Cameron added that the "room for doubt" about whether the Syrian regime was using chemical weapons against rebels, including the nerve agent sarin, "continues to diminish".
"There's an urgent need to start a proper negotiation to force a political transition and to bring this conflict to an end, and I will be flying to Sochi on Friday to meet with President Putin to discuss this issue further," Cameron told the House of Commons.
He added: "There is a growing body of limited but persuasive information showing that the regime has used and continues to use chemical weapons including sarin, and the room for doubt about this continues to diminish."
Cameron said he discussed the Syrian crisis with US Secretary of State John Kerry on Wednesday morning, the day after the American agreed in talks in Moscow with Putin to hold an international conference in search of peace.
Russia is the most powerful ally of Syrian President Bashar al-Assad, and Washington, London and other Western powers want Putin to use his influence to help end the bloodshed.
Cameron's trip to Russia has been planned for several weeks but was subject to a media blackout.