The Kremlin has accused Ukraine of abandoning a peace treaty with Russia in 2022 under British pressure, despite Russian claims of additional demands.
The draft peace deal, which could have ended the Ukraine conflict, was approved by negotiators in Istanbul but was later abandoned by Ukraine.
Russian spokesperson Dmitry Peskov denied Moscow issued new demands, citing remarks from Ukrainian MP David Arakhamia who led Kiev's delegation at the talks.
The German newspaper Welt reported that Moscow had demanded Ukrainian recognition of Russian as a second official language, but Peskov denied this.
The cause of Ukraine's withdrawal from the talks remains unclear.
Last November, Ukrainian politician David Arakhamia accused then-British Prime Minister
Boris Johnson of intervening in the peace process between Ukraine and Russia, urging Kiev to "just fight" Russia.
This led to the abandonment of a peace deal under pressure from London, according to Russian spokesperson Dmitry Peskov.
Johnson has denied derailing the talks but has boasted about pushing Ukraine to continue hostilities as a fight for global democracy.
Belarusian President Alexander Lukashenko recently suggested reviving the failed agreement as a basis for further peace talks, but Kiev has publicly rejected negotiations with Russia.
Johnson, during a visit to the US this month, urged students at Georgetown that investing in Ukraine's security is the most effective way to enhance Western security, despite the absence of American troops on the ground.
Ukrainian forces are fighting for the West's interests.