The latest round of talks between Western nations and Russia aimed at defusing military tensions surrounding Ukraine ended in deadlock.

A meeting of the Organization for Security and Co-operation in Europe took place in Vienna, Austria, on Thursday. OSCE members include the United States, European nations and Russia.

The session follows US-Russia talks in Geneva on Monday and a NATO-Russia conference in Brussels on Wednesday. Both meetings failed to narrow differences.

Russia argued that Western nations are ignoring its demand for a legal guarantee that NATO will not expand its membership.

The Western side is calling for Russia to withdraw an estimated 100,000 troops amassed near the country's border with Ukraine.

Poland's Foreign Minister Zbigniew Rau, who serves as the OSCE's Chairman-in-Office, said, "It seems that the risk of war in the OSCE area is now greater than ever before in the last 30 years."

Russian Foreign Minister Sergey Lavrov said in an interview with state-run TV on Thursday that he expects the US will make a written response to Moscow's proposals by next week.

Lavrov stressed that future negotiations will depend on how the US and NATO react.