Russian President Vladimir Putin on Friday hailed his country's close ties with China, in a meeting with Chinese counterpart Xi Jinping ahead of the opening of the Winter Olympic Games in Beijing.

The two leaders met in the Chinese capital as their countries seek to deepen relations in the face of mounting criticism from the West.

Moscow's ties with Beijing are "developing progressively along the path of friendship and strategic partnership", Putin said in televised remarks at the start of their meeting.

"They are of a truly unprecedented nature," the Russian leader said, describing relations as an "example of a dignified relationship".

He said ahead of the meeting that Moscow had prepared a new contract for the supply of 10 billion cubic metres of natural gas to China from Russia's Far East.

In the days leading up to the trip, a Kremlin aide said the two leaders also would sign a document that reflected their "common views" on security and other issues.

Later in the day, Putin will take part in the opening ceremony of the Olympic Games. 

While Russian officials are banned from attending international sporting competitions over a doping scandal, they may attend if invited by the head of state of the host country. 

Russian athletes are allowed to compete as neutrals -- without the Russian flag or anthem -- if they can prove their doping record is clean.

Beijing and Moscow have denounced a diplomatic boycott of the Winter Olympics by several countries over what Western governments argue are widespread rights abuses in China.