Russian, Ukrainian and US negotiators will hold talks in the United Arab Emirates later, in what officials say will be the first meeting attended by all three countries since Moscow launched its full-scale invasion nearly four years ago.
The Kremlin confirmed Russian officials would attend the talks following a meeting between President Vladimir Putin and US envoys in Moscow.
Russia described those talks as useful in every respect, but said a long-term peace deal could not be reached until territorial issues had been resolved.
Ukrainian President Volodymyr Zelensky said he regarded the Abu Dhabi talks as a step - hopefully towards ending the war.
Present at the Thursday night meeting with Putin and two other Russian aides were three US representatives, including Steve Witkoff, and Donald Trump's son-in-law Jared Kushner.
Kremlin aide Yuri Ushakov said the talks were substantive, constructive and very frank, but reiterated that any agreement for durable peace would not be possible without resolving territorial issues.
Until this is achieved, Russia will continue to consistently pursue the objectives of the special military operation, he said.
Ushakov added that Putin emphasised Russia was sincerely interested in a diplomatic solution.
Without resolving the territorial issue according to the formula agreed upon in Anchorage, there is no hope of achieving a long-term settlement, he said.
Witkoff last year said that Russia had agreed to allow the US and Europe to give Ukraine robust security guarantees as part of a potential peace deal.
After meeting with Trump in Davos, Zelensky also made clear that the future status of territory in eastern Ukraine remained unsolved ahead of talks in Abu Dhabi.
It's all about the land. This is the issue which is not solved yet, Zelensky told reporters in Davos.
On Friday, he told journalists: The Donbas issue is key. It will be discussed as will be the modality of how the three sides see it.
Zelensky said last month that a 20-point US plan to end the war was 90% ready and that Ukraine's position on Donbas was different from Russia's.
He has offered to withdraw troops by up to 40km from the region in order to create an economic zone in Donbas, if Russia does the same.
Both Ukraine and Russia have reported drone attacks overnight, with ongoing consequences for civilians as recent Russian strikes have left much of Ukraine without heating or power during severe winter conditions.
