Communist China’s state-run media is reveling in the latest political challenge to Taiwan’s president, Lai Ching-te, who is facing an impeachment bid from two opposition parties over his failure to promulgate a domestic spending bill.

While unlikely to overcome political and procedural hurdles, the impeachment effort seeks to exploit low approval ratings for Mr. Lai, who this week incurred Beijing’s wrath with the announcement of a record arms purchase from America.

Global Times, an organ of the mainland’s Communist Party, quoted a university professor, Zheng Jian, suggesting the bid was a response to Mr. Lai’s “arbitrary and dictatorial” practices and public dissatisfaction with his “persistent secessionist provocations and belligerent acts.”

Independent media on Taiwan, seat of the Free Chinese government since 1949, offered a more prosaic explanation, saying the opposition parties moved after Mr. Lai refused this week to promulgate a legislative amendment that would have allowed local governments to receive a larger share of government revenue.

A report in the Taipei Times noted that the impeachment bid has little chance of success, even in the unlikely event it wins the necessary approval from two-thirds of lawmakers. It would then go forward to  the Constitutional Court which, with seven of its 15 seats currently vacant, lacks the necessary quorum to act on any referral.

Nevertheless, the initiative raises the profile of the opposition Nationalist Party, or KMT, which has long been more open to friendly dialogue with Beijing than the more confrontational and independence-minded Taiwan People’s Party of Mr. Lai.

The KMT’s new chairwoman, Cheng Li-wun, has repeatedly voiced her support for a 1992 understanding with Beijing under which the KMT and the Chinese Communist Party acknowledge that there is “one China,” with each side having its own interpretation of what “China” means.

Ms. Cheng is also said to be seeking an early meeting with the president of Communist China, Xi Jinping, although Beijing is reportedly demanding that the KMT first use its legislative power to block the $11.1 billion American arms sale to Taiwan announced this week.

That sale, covering weapons ranging from anti-tank and anti-ship missiles to parts for helicopters, is the largest in a long list of American arms sales to the democratic island over the past few decades. The Beijing government’s defense ministry responded that it will “take forceful measures” to defend the mainland’s sovereignty.

The Beijing government also said it had lodged “stern representations” with the American administration demanding a halt to the sales. But notably, it did not threaten to cancel a planned visit to Beijing by President Trump in April or a reciprocal visit to America by Mr. Xi later next year.