A Chinese mainland spokesperson on Wednesday expressed strong opposition to U.S. signing into law of a defense spending act that has content related to Taiwan.

The United States has no right to interfere in Taiwan-related issues, which fall within China's domestic affairs, said Ma Xiaoguang, spokesperson for the Taiwan Affairs Office of the State Council, in response to U.S. President Joe Biden's signing into law of the U.S. National Defense Authorization Act for Fiscal Year 2022.

"No person or force can stop our righteous actions to thwart 'Taiwan independence' activities and safeguard national sovereignty and territorial integrity," Ma said at a press conference.

Attempts of Taiwan's Democratic Progressive Party authority to look for U.S. support for the independence agenda will fail, he said.

Also at the press conference, Ma urged Japan to adhere to the "one-China" principle, abide by four political documents between the two countries and prudently handle Taiwan-related issues.

When commenting on Taiwan's participation in regional economic cooperation, he reiterated the "one-China" principle and urged politicians in certain related countries to refrain from sending any wrong signals to "Taiwan independence" separatist forces.