United Nations, March 15 (IANS): The UN Security Council is expected to hold an emergency meeting Saturday to vote on a draft resolution on Ukraine drawn up by the US and backed by Western countries, diplomats and UN officials said here.

"There will be an open meeting of the Security Council tomorrow (Saturday) in the Security Council Chamber," Xinhua quoted the UN spokesperson's Office as saying in a message to reporters Friday.

The meeting was called at the request of the US permanent mission to the UN, which is firmly against the March 16 referendum on the status of the Russian-speaking Crimea, diplomats said.

Russia, one of the five permanent council members, is expected to veto the resolution, which intends to declare that the planned referendum in Crimea "can have no validity", and urge nations and international organisations not to recognise it, diplomats said.

The council meeting comes after talks in London between US Secretary of State John Kerry and Russian Foreign Minister Sergei Lavrov on the Ukrainian crisis made no progress Friday.

Earlier, UN Secretary-General Ban Ki-moon said that "it is clear that we are at a crossroads" in the Ukrainian crisis and "if positions continue to harden and rhetoric continues to sharpen, there is great risk of a dangerous downward spiral".

The interim Ukrainian government insists the referendum is unconstitutional since a Ukrainian-wide ballot was necessary for such secession.