Beijing's top diplomat told President Vladimir Putin that China and Russia must work to strengthen cooperation in the face of a "complex international situation", Chinese state media reported Thursday.

Speaking at a meeting with Putin in Saint Petersburg, at which the Russian leader accepted an invitation to visit China next month, Wang Yi said the "world is rapidly moving toward multipolarity".

"Economic globalization is progressing against headwinds, unilateral actions are unsustainable, and hegemonism is not popular," Wang said, according to an English readout by Beijing's Xinhua news agency.

"Both sides need to strengthen their multilateral strategic cooperation, protect their legitimate rights and interests, and make new efforts to promote the international order toward fairness and justice," he added.

Putin, in response, told Wang "our positions coincide regarding the emergence of a multipolar world", according to a readout from the Kremlin.

He also said he had "gladly accepted" Chinese leader Xi Jinping's invitation "to visit China this October as part of a major event to promote the Belt and Road Initiative".

Putin is widely expected to attend next month's third Belt and Road Forum for International Cooperation in Beijing, which will mark the 10-year anniversary of China's international infrastructure project.

Precise dates for the summit have not been made public.

Asked Thursday by AFP to confirm when precisely Putin's visit would take place, Beijing said it was "keeping close communication with its partners along the Belt and Road".

"We welcome countries and partners actively participating in the Belt and Road Initiative to come to Beijing to discuss cooperation plans and seek common development," foreign ministry spokesperson Mao Ning said. 

China and Russia describe each other as strategic allies, with both countries frequently touting their "no limits" partnership and economic and military cooperation.

They came even closer after Russia's invasion of Ukraine in February last year, which China has refused to condemn.

The Kremlin has sought to deepen ties with China after the start of its Ukraine offensive, which has thrown Moscow into increasing isolation.

China has sought to position itself as a neutral party in the Ukraine conflict, while offering Moscow a vital diplomatic and financial lifeline.

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