London: China has condemned the nearly week-long visit of British lawmakers to the self-governed island Taiwan, which Beijing regards as its own.

The delegation has met high-level officials, including Taiwan's foreign minister, Joseph Wu. The committee met Taiwan's Premier Su Tseng-chang on Thursday and was scheduled to see President Tsai Ing-Wen on Friday.

On Thursday, the Chinese embassy in the UK said the MPs' visit to the "Taiwan region of China" took place despite Beijing's "firm opposition".

"This is a flagrant violation of the one-China principle and a gross interference in China's internal affairs," a Chinese spokesperson said. Taiwan is self-ruled, however, China sees it as a breakaway province that will eventually unite with it.

Beijing's statement added that any moves to undermine China's interests would be met with "forceful responses".

The embassy spokesperson said the Chinese side has made solemn representations with the United Kingdom. "Taiwan is an inalienable part of China's territory, and the Taiwan question is purely China's internal affair," the spokesperson added.

Members of the British Foreign Affairs Committee on Tuesday arrived in Taiwan. They are a part of an investigation into Britain's shifting economic and political focus towards the Indo-Pacific region, following its exit from the European Union.

Taiwan's Ministry of Foreign Affairs tweeted that Wu held a banquet for the UK delegation and spoke about "increasing authoritarian threats" and "worrying issues at home and abroad".

"Minister Wu held a banquet for the #UK @HouseofCommons delegation to #Taiwan. He compared notes with the MPs on increasing authoritarian threats and other worrying issues at home and abroad. All concurred that cooperation between democracies is more vital than ever," the Taiwanese Foreign Ministry tweeted on December 1.

Before the visit, committee chair Alicia Kearns said the Indo-Pacific, and the strength of relationships in the region are of huge importance to the country, Al Jazeera reported. "Within the Indo-Pacific region, Taiwan's voice is unique and invaluable," she stated.

The statements by China follow a speech by UK Prime Minister, Rishi Sunak, earlier this week wherein he hinted that the so-called "golden era" of British ties with China was over.

The UK MPs' visit is one of a number of recent incidents to cause friction that include the detention of a British journalist covering protests in China, and the involvement of a senior Chinese envoy in the Manchester consulate violence.

A controversial visit in August by senior US politician Nancy Pelosi had similarly enraged Beijing.

The then-speaker of the US House Nancy Pelosi's visit to Taiwan was followed China's biggest-ever war games in the seas around Taiwan, further straining ties between Beijing and Washington.