China's special envoy for Eurasian affairs, Li Hui, said on Friday that he believes neither Ukraine nor Russia have "firmly" shut the door to talks, despite difficulties in getting negotiations going now.

Giving a media briefing on his European tour last month, Li said the Russian side has appreciated China's desire and efforts to promote a peaceful settlement of the Ukraine crisis.

In May, Li completed a 12-day tour of Kyiv, Warsaw, Paris, Berlin, Brussels and Moscow in a bid to find common ground for an eventual political settlement of the Ukraine war.

"The risk of escalation of the Russia-Ukraine war is still high," Li said, adding that all sides must take concrete measures to "cool down the situation" ensure the safety of nuclear facilities.

"As long as it's conducive to easing the situation, China is willing to do anything," he said.

Li, ambassador to Russia from 2009 to 2019, is the most senior Chinese official to visit Ukraine since Russia invaded in February 2022.

His trip came ahead of an expected counteroffensive by Ukraine to recapture territory seized by Russia.

His highly scrutinised trip did not appear to lead to any diplomatic breakthrough, however.

China has close ties with Russia and Beijing has never condemned Russia's intervention or even called it an invasion.

China says it is a neutral party in the war.

The Kremlin has said Russia was open to negotiations to end the conflict.

Ukraine says Russian troops must leave every inch of its territory including the four annexed regions and the Crimean peninsula, which Moscow unilaterally annexed from Ukraine in 2014, before a peace plan can be discussed. (Reporting by Laurie Chen, Liz Lee and Ethan Wang; Editing by Christina Fincher, Robert Birsel)