The UN-hosted negotiations on the Syrian conflict planned for February 8 in Geneva have been postponed until the end of that month, Russian Foreign Minister Sergey Lavrov has said.

"The date of February 8 has been put back until the end of next month," Lavrov said at a meeting on Friday with Syrian opposition groups in Kazakhstan that ended on Tuesday without a major breakthrough.

The UN, however, said it could not confirm the delay of the next round of talks between the Syrian government and the opposition.

"There is no confirmation that the February talks are postponed," said Yara Sharif, a spokeswoman for UN special envoy Staffan de Mistura. "We're going to be sure when the special envoy is back" from talks next week with UN Secretary General Ban Ki-moon.

The main opposition groups stayed away from the Moscow meeting with Lavrov, as the Kremlin seeks to impose its influence as the key power broker in Syria on the back of its game-changing military support for President Bashar al-Assad.

READ MORE: Astana summit - Opposition sets demands for new talks

Representatives from armed opposition groups and Damascus were expected to hold their first face-to-face talks in Astana, the Kazakh capital. But the rebels refused, citing truce violations, and mediators were forced to shuttle between the two sides.

Key players Russia, Turkey and Iran backed the talks and the main result was an agreement by the three sides to try to shore up a shaky ceasefire on the ground in the war-torn country.

The latest peace initiative to halt fighting comes after the Syrian army, backed by Russian and Iranian firepower, dealt rebels a crushing blow by forcing them out of eastern Aleppo last month.

The Syrian Observatory for Human Rights, a UK-based monitoring group, estimates that more than 310,000 people have been killed in Syria since 2011.