(CNN)A US Congressional delegation to Asia has been postponed after House Speaker Nancy Pelosi tested positive for Covid-19.
The announcement followed a warning by China that it would take strong measures if the trip included a visit to Taiwan, as media reports in the region had claimed.
Pelosi's deputy communications director Drew Hammill said in a tweet on Thursday that the planned Congressional delegation to Asia, to be led by Pelosi over the two-week Congressional break, "will be postponed to a later date."
"After testing negative this week, Speaker Pelosi received a positive test result for Covid-19 and is currently asymptomatic. The Speaker is fully vaccinated and boosted, and is thankful for the robust protection the vaccine has provided. The Speaker will quarantine consistent with CDC guidance, and encourages everyone to get vaccinated, boosted and test regularly," Hammill tweeted.
Reports by some Japanese and Taiwanese media that Pelosi planned to visit Taiwan after a stop in Japan this weekend -- though not confirmed by Pelosi's office or Taiwan's government -- had earlier sparked a warning from Beijing that such a visit would severely impact China-US relations.
Chinese Foreign Ministry spokesperson Zhao Lijian said Thursday that China "resolutely opposes all forms of official contact between the US and Taiwan" and urged Washington to "immediately cancel Speaker Pelosi's plan to visit Taiwan."
"If the US insists on having its own way, China will take firm and strong measures to resolutely safeguard its sovereignty and territorial integrity. All possible consequences that arise from this will completely be borne by the US side," he added, without providing details.
The Chinese Communist Party has long claimed democratically ruled Taiwan as part of its territory and has repeatedly vowed to "reunify" with the island of 24 million people -- by force if necessary -- despite having never governed it. Washington officially recognizes Beijing rather than Taipei, but is committed to provide Taiwan with the means to defend itself.
Pelosi's positive test result comes after a wave of positive tests among lawmakers on Capitol Hill this week.
She was at the White House on Wednesday seen next to President Joe Biden as he signed a bill into law. The House physician told CNN that members who attended had to have a negative test within 24 hours of the event.
Pelosi, the top House Democrat, is 82 years old. As speaker of the House, she is second in the line of presidential succession behind the vice president.
Biden, 79, tested negative on Wednesday night, the White House said.