Ankara: Turkey and Russia have agreed on a proposal for a general ceasefire in Syria and will aim to put it into effect by midnight on Wednesday, Turkeys Foreign Minister Mevlut Cavusoglu said.
But he still insisted that Syrian president Bashar al-Assad must eventually go, a precondition for talks that Russia has always opposed.
There was also no sign that the mainstream Syrian opposition groups agreed to the ceasefire, and it appears likely there will be disagreement about the territory to be covered by any ceasefire. The rebel groups will want it to extend to the Damascus countryside, something that Russia opposes.
A senior official in the opposition said they had not received the details of any official deal and denied that they agreed to a ceasefire agreement.
"The details of the ceasefire have not been presented officially to the opposition factions yet, and there is no agreement at this point," the official said.
Russia, Iran and Turkey said last week they were ready to help broker a peace deal after holding talks in Moscow where they adopted a declaration setting out the principles any agreement should adhere to.
"There are two texts ready on a solution in Syria. One is about a political resolution and the other is about a ceasefire. They can be implemented any time," Cavusoglu told reporters at the presidential palace in Ankara.
He said Syria's opposition would never back Assad.
"The whole world knows it is not possible for there to be a political transition with Assad, and we also all know that it is impossible for these people to unite around Assad."
Last week, Russia's Foreign Minister said Moscow, Tehran and Ankara agreed that the priority in Syria was to fight terrorism and not to remove Assad's government.
Turkey's state-run Anadolu news agency said earlier on Wednesday that Moscow and Ankara had agreed on a proposal towards a general ceasefire. The Kremlin said it could not comment on the report, and it may be the Turks have announced something prematurely.
Any ceasefire would exclude groups labelled as terrorists by the two countries, allowing attacks to continue against the Islamic State and others. Turkey has said the talks must not include the Syrian Kurdish Democratic party or its military arm (YPG).
Arrangements for the Russian-led talks are vague, but Moscow has said they will take place in Kazakhstan. Astana, the Kazakh capital, staged Syrian peace talks in 2015, but critics said they excluded most of the mainstream opposition and so were largely pointless.
Russia's Foreign Minister said on Tuesday the Syrian government was consulting with the opposition before possible peace talks, while a Saudi-backed opposition group said it knew nothing of the negotiations but supported a ceasefire.
The talks would exclude groups labelled as terrorists by Moscow, a group that would exclude Al Nusra, the Al Qaeda franchise in Syria, and the IS, the Sunni group based in Raqqa in north-east Syria.