Russia said on Friday that any placement of British military assets in Ukraine under a new 100-year partnership agreement between Kyiv and London would be of concern to Moscow.

Kremlin spokesman Dmitry Peskov was asked about the possibility of Britain setting up military bases in Ukraine under the agreement announced on Thursday by Ukrainian President Volodymyr Zelenskyy and British Prime Minister Keir Starmer.

"Given that Britain is a NATO country, the advancement of its military infrastructure towards our borders is certainly a rather worrying element. In any case, it will be necessary to further analyze what will happen," Peskov said.

At Thursday's talks in Kyiv, Zelenskyy said he had spoken to Starmer about Kyiv's desire for Western peacekeeping troops to be deployed in Ukraine if the war with Russia ended.

Asked if Britain would contribute troops, Starmer said in an interview with Sky News that he had discussed this with Zelenskyy and other allies and Britain would "play our full part."

Peskov said Moscow also took a "negative" view of the prospect of British cooperation with Ukraine in the Sea of Azov, which he described as Russia's "internal sea."

The Azov Sea is bordered by southwest Russia, parts of southern Ukraine that Russia has seized in the war, and the Crimean peninsula that Moscow annexed from Ukraine in 2014.