China warned the United States to "stop interfering" in the Winter Olympics on Thursday, a week before the controversy-hit Games are due to start in Beijing.

As the first city to host both a Winter and Summer Games, Beijing has been hoping to turn next week's sports extravaganza into a soft power triumph. 

But the lead-up has been clouded by a US-led diplomatic boycott over China's human rights record, particularly its policy towards its Uyghur Muslim minority in the Xinjiang region that Washington has labelled a "genocide".

China's top diplomat Wang Yi spoke with his US counterpart Secretary of State Antony Blinken, according to a foreign ministry statement Thursday.

"The most urgent priority right now is that the US should stop interfering in the Beijing Winter Olympics," Wang said during the call.

The US government and lawmakers in five Western countries have declared China's treatment of the Uyghurs in its Xinjiang region a "genocide", with France's National Assembly the latest to do so this month.

Rights campaigners have accused the International Olympic Committee of turning a blind eye to what they say is a litany of abuses in China, including in Tibet and its ongoing clampdown on free expression in Hong Kong.

Activists grabbed the spotlight at the lighting ceremony in Greece by unfurling a Tibetan flag and a banner that read "no genocide".

Beijing has repeatedly railed against what it has dubbed the "politicisation" of sport and the International Olympic Committee has made similar calls to separate sport and world affairs.

China's President Xi Jinping had a rare pandemic-era encounter with Olympic chief Thomas Bach this week.

With Beijing cracking down on dissent before the Games, AFP also spoke to multiple human rights activists and academics in China who had been blocked on WeChat messaging app accounts restricted in recent weeks.

Authorities have also detained two prominent human rights activists, while a third rights lawyer missing since early December is believed by relatives to be in secret detention. 

Crunch points 

Tensions between Beijing and Washington have soared in recent years on several fronts, including trade and technology.

In the call, the officials also discussed the growing tensions in Europe over Ukraine, with Wang telling Blinken that Russia's security concerns "should be taken seriously".

"All parties should completely abandon the Cold War mentality and form a balanced, effective and sustainable European security mechanism through negotiation," Wang said.

The State Department's readout of the call made no mention of the Olympics and instead focused on Ukraine. 

Global concerns are growing over a potential Russian invasion of Ukraine, as tens of thousands of Russian troops have been stationed at the border in recent weeks.

In response, the US and other NATO member states have been conducting intense diplomacy with Russian President Vladimir Putin in recent days, as well as providing military reinforcement to Ukraine. 

The US and its NATO allies have said they are ready for any eventuality.

Russia, which has a troubled historical relationship with Ukraine, has fuelled an insurgency in the former Soviet republic's east that has killed more than 13,000 people since 2014.

Moscow has denied planning to invade Ukraine but has also said it wants guarantees that the country will not join NATO.