United States House of Representatives Speaker Nancy Pelosi should have canceled her planned visit to Taiwan rather than delayed it, a Chinese official said on Wednesday, warning that resolute countermeasures will be taken against acts that seriously undermine China's sovereignty and territorial integrity.

Ma Xiaoguang, a spokesman for the Taiwan Affairs Office of the State Council, made the remarks at a news conference in Beijing when commenting on the invitation to Pelosi by the island's Democratic Progressive Party authority.

Taiwan media reported earlier last week that Pelosi was scheduled to lead a delegation that was due to arrive in Taiwan on Sunday, which would have made her the first sitting US House speaker to visit the island since 1997.

However, the visit was postponed after she tested positive for COVID-19 last week and protests from Beijing officials.

Pelosi announced on Monday that she has tested negative for COVID-19 and would end isolation on Tuesday, and the DPP authority has been working on the invitation.

Ma called on the US to abide by the one-China policy and the stipulations of the three China-US joint communiques.

He said that the US should fulfill its commitment to China on the Taiwan question, stop playing the Taiwan card and stop using the Taiwan question to contain China.

He also urged the DPP authority to stop provocative attempts to collude with foreign forces on "independence".

In another provocative action, US Senator Josh Hawley introduced last week the Taiwan Weapons Exports Act, which would speed up the delivery of US weapons to Taiwan, following the $95 million arms sale the US approved to Taiwan to boost its "air defense".

In response, Ma said the US' arms sale to Taiwan is no different from "tying a bomb to every Taiwan compatriot".

Taiwan's "defense authority "issued on Tuesday a so-called defense manual, which hypes up the issue of "seeking shelter during wartime", causing anxiety among local residents, the island's media reported.

Ma denounced such measures, saying that "Taiwan independence" means the loss of peace and the advent of disaster, and the DPP's provocations against the mainland are the biggest threat to security across the Taiwan Straits.

"For their own selfish gains, the DPP is binding the Taiwan people to the chariot of 'independence', which will only push the Taiwan people into the abyss of disaster," he said.

The DPP authority has taken advantage of the Ukraine crisis recently, Ma said, adding that it is following the Western anti-China forces in hyping up the "military threat" from the mainland and exacerbating tension between the two sides.

"The DPP authority wants to take the opportunity to internationalize the Taiwan question," he added.