Russia will seek guarantees that Nato will exclude Ukraine from membership and that Ukraine will remain neutral in any peace deal, a Russian deputy foreign minister said.
"We will demand that ironclad security guarantees become part of this agreement," Alexander Grushko told Russian media outlet Izvestia.
"Part of these guarantees should be the neutral status of Ukraine, the refusal of Nato countries to accept it into the alliance," he said.
It comes as US President Donald Trump has said he will speak to his Russian counterpart Vladimir Putin on Tuesday, as talks continue over a possible ceasefire in the three-year war in Ukraine.
Speaking on Air Force One on Sunday evening, Trump said: "A lot of work's been done over the weekend. We want to see if we can bring that war to an end."
"We will be talking about land. We will be talking about power plants," Trump said when asked about concessions.
Trump added that he was already discussing "dividing up certain assets" between Russia and Ukraine.
The US and Ukraine have agreed to propose a 30-day ceasefire to Russia.
While Putin said that he supported a ceasefire, he also set out a list of tough conditions for achieving peace.
One of the areas of contention is Russia's western Kursk region, where Ukraine launched a military incursion last August and captured some territory.
Putin has claimed Russia is fully back in control of Kursk, and said Ukrainian troops there "have been isolated".
He has also raised numerous questions about how a ceasefire could be monitored and policed along the frontline in the east.
Meanwhile, Ukraine's President Volodymyr Zelensky has accused Putin of trying to "sabotage" diplomatic efforts to secure an immediate ceasefire.
US envoy Steve Witkoff, who met with Putin on Thursday in Moscow, earlier declined to answer a question on how Russian-occupied land in Ukraine could be addressed in a potential deal, during an interview with CNN. Russia currently controls around a fifth of Ukraine.
During his election campaign, Trump repeatedly promised to end the war, which began with Russia's full-scale invasion of its neighbour in 2022, on "day one" of a new administration.
Less than a month after he was inaugurated, Trump had call with Putin that reportedly spanned 90 minutes about immediately starting negotiations on ending the war.
