China's top diplomat, Wang Yi, begins a four-day trip to Russia during which both nations are expected to pledge deeper mutual political trust, readying for a possible landmark visit by President Vladimir Putin to Beijing in October.

Wang, who heads the foreign ministry as well as the ruling Communist Party's foreign affairs office, will meet Security Council Secretary Nikolai Patrushev for annual security talks, the Chinese foreign ministry said in a statement.

The veteran diplomat's talks with counterpart Sergei Lavrov will cover a "wide range of issues" including "contacts at higher and the highest levels," the Russian foreign ministry said last week.

Wang is expected to lay the groundwork for Putin's visit to the Chinese capital for the third Belt and Road Forum after an invitation by President Xi Jinping during a high-profile visit to Moscow in March.

Putin attended China's first two Belt and Road Forums in 2017 and 2019.

But he is not known to have travelled abroad since the International Criminal Court (ICC) issued an arrest warrant against him on grounds of illegally deporting hundreds of children from Ukraine.

On Sept. 1, Putin said he expected to meet Xi soon, but did not explicitly confirm that he would travel to China again.

The warrant, issued just days before Xi visited Russia, obligates the court's 123 member states to arrest Putin and transfer him to the Hague for trial if he enters their territory.

However, China is not a party to the Rome Statute that led to the establishment of the ICC in 2002.

The visit will also see a detailed exchange of views on issues including Ukraine, ministry spokeswoman Maria Zakharova said last week.

Wang last visited Russia in February on the eve of the one-year anniversary of Russia's invasion of Ukraine, alarming the United States, which accused the two nations at the time of sharing a vision in which "borders could be redrawn by force".

Ahead of this week's visit, Wang travelled to Malta for hours of "constructive" talks with White House national security adviser Jake Sullivan.

The weekend talks were the latest in a series of high-level meetings between U.S. and Chinese officials that could lay the foundation for a meeting this year between Xi and U.S. President Joe Biden.