The Kremlin earlier had downplayed expectations for the talks by saying the two sides were far apart in their visions on how to end the more than three-year war.

"The delegation will be headed by Rustem Umerov and will include representatives of Ukrainian intelligence, Ukraine's foreign ministry, and the office of the president," Zelensky wrote on social media.

Moscow has not yet announced the composition of its team for the talks.

Its delegation at the previous round was led by a hawkish historian and the current head of the Russian Union of Writers Vladimir Medinsky, whom Ukraine described as not a real decision-maker.

Zelensky said Kyiv was ready to "secure the release of our people from captivity and return of abducted children, to stop the killings, and to prepare a leaders' meeting," outlining potential topics for discussion on Wednesday.

Ukrainian and Russian delegations met in Istanbul on May 16 and on June 2 as Washington stepped up pressure for a deal, but no breakthroughs were made.

Ukrainian and Russian negotiators only agreed to exchange prisoners and soldiers' bodies. Russia has since launched intense air attacks on Ukraine and seized more frontline territory.

Kyiv said the increased pressure by Moscow showed it was not serious about halting the offensive it launched in February 2022.