The advanced team’s arrival followed talks at the end of January between WHO director general Tedros Adhanom Ghebreyesus and Chinese President Xi Jinping.

More experts are expected to follow as part of the mission but it is not known when they will land in China.

Nancy Messonnier, director of the US’ National Centre for Immunisation and Respiratory Diseases, said American specialists seeking to join the WHO’s mission to China had not yet received any assistance, Bloomberg reported.

“We haven’t been invited yet,” she said on Wednesday, a week after the Chinese foreign ministry confirmed that the United States had offered to send specialists as part of the mission.

The US Centres for Disease Control and Prevention, which oversees the immunisation centre, did not respond to requests for details about the US experts.

Marcia Poole, director of external relations for WHO health emergencies, said arrangements were still being finalised so the mission’s team could not be confirmed.

On Saturday, the Chinese foreign ministry said China “welcomes all foreign experts, including those from the US, to join” the joint WHO mission.

But earlier in the month, it had also accused Washington of having “inappropriately overreacted” to the outbreak with strict travel restrictions for China and for having “not provided any substantive aid”.

Chinese foreign ministry spokesman Geng Shuang said on Thursday that the WHO’s advance team would discuss arrangements with its Chinese counterparts.

The team’s main mission would be to “conduct in-depth exchanges on the epidemic situation and prevention and control efforts, to provide recommendations and inputs for China and other affected countries in the world in their next steps for epidemic prevention”, Geng said.

Adam Ni, co-editor of the China analysis newsletter China Neican, said the composition of the WHO team would be influenced by Beijing’s political considerations, including not wanting to appear to need help, particularly from the US.

“China and the US are still very much competitors, with the rising intensity of strategic competition and rhetoric, so in this environment, I see it highly unlikely that the Chinese government will accept substantive US aid,” Ni said.

“This might reduce the US role in the WHO effort in China, but then again this is because of pure politics and the perception of weakness that Beijing wants to avoid.”