Speaking during a meeting in Taipei with US Senator Marsha Blackburn, Tsai labelled the two countries as "authoriatarian" and Blackburn said she "looked forward to continuing to support Taiwan as they push forward as an independent nation".

Blackburn's visit would be the third high-profile visit by American politicians to Taiwan since US House Speaker Nancy Pelosi's visit earlier this month which angered China, which responded with largest ever military exercises around Taiwan, pressing in hundreds of aircraft, warships, and launching missiles, which not just landed close to Taiwan's shore but also flew over the island and even landed in Japan's economic zone's waters.?

China claims Taiwan as its own territory whereas Taiwan identifies itself as an independent nation. China considers Taiwan a breakaway province and aims to unify it with the mainland one day. For the purpose of unification, China has not ruled out the use of force. China's recent military drills were seen by some as a rehearsal of future military action against the island, which US military leaders say could come within the next few years.

Since China sees Taiwan as its territory, it sees high-level visits and support to Taiwan's independence —such as by Blackburn— a violation of its claim and interferance in its internal affairs.?

"These developments demonstrate how authoritarian countries are disrupting and threatening the world order," said Tsai in her meeting with Blackburn.

In their meeting, Tsai and Blackburn underscored the importance of economic links, especially in the semiconductor sector, where Taiwan is a world leader and the US is seeking greater investment at home.?

Blackburn arrived in Taipei late Thursday after visiting Fiji, the Solomon Islands and Papua New Guinea as part of a U.S. push to “expand our diplomatic footprint in the area”, her office said in a statement.?

“The Indo-Pacific region is the next frontier for the new axis of evil. We must stand against the Chinese Communist Party," said Blackburn.

During her three-day visit, Blackburn is also due to meet with the head of Taiwan's National Security Council.?

“I just landed in Taiwan to send a message to Beijing — we will not be bullied. The United States remains steadfast in preserving freedom around the globe, and will not tolerate efforts to undermine our nation and our allies," said Blackburn on Friday.?

"It is a great honor to meet with President Tsai to reiterate support for Taiwan's freedom and future achievements," she further said of her meeting with Tsai.

Besides Blackburn and Pelosi, a five-member US Congressional delegation and an American state's governor have also visited Taiwan this month.

The five-member delegation was led by Democratic Senator Ed Markey. The other members were Republican Rep. Aumua Amata Coleman Radewagen, a delegate from American Samoa, and Democratic House members John Garamendi, Alan Lowenthal, and Don Beyer.

Besides them, Indian Governor Eric Holcomb also began a visit to Taiwan on Monday. His four-day visit will focus on economic exchange, particularly semiconductors, according to a statement from his office.?

Due to the separation of powers in the US government, the executive branch has no authority to prevent lawmakers or state leaders from making such foreign visits and Taiwan benefits from strong bipartisan support in Washington. China, whose ruling Communist Party wields total control over the country's politics, refuses to acknowledge that fundamental principle.?

US State Department spokesperson Vedant Patel said members of Congress and elected officials “have gone to Taiwan for decades and will continue to do so", saying it was in line with US policy to only maintain formal diplomatic ties with Beijing.?

“We're going to continue to take calm and resolute steps to uphold peace and stability in the region and to support Taiwan in line with our longstanding policy," Patel said at a briefing on Thursday.?

Taiwanese Foreign Minister Joseph Wu told reporters on Friday that “China's motivation is to destroy the Taiwan Straits' status quo, and after this they want to cut down on Taiwan's defensive space".?

Taiwan is seeking stepped-up defense cooperation and additional weaponry from the US, along with closer economic ties.?

Washington has no official diplomatic ties with Taipei in deference to China, but remains the island's biggest security guarantor, with US law requiring it ensure Taiwan has the means to defend itself and to regard threats to the island as matters of “grave concern”.?

Taiwan and China split in 1949 after a civil war and have no official relations but are bound by billions of dollars of trade and investment.?

China has increased its pressure on Taiwan since it elected independence-leaning Tsai as its president. When Tsai refused to endorse the concept of a single Chinese nation, China cut off contact with the Taiwanese government.

US congressional visits to the island have stepped up in frequency in the past year.

On Thursday, the executive branch of Taiwan's government laid out plans for a 12.9 per cent increase in the Defense Ministry's annual budget next year. The government is planning to spend an additional 47.5 billion New Taiwan dollars ($1.6 billion), for a total of 415.1 billion NTD ($13.8 billion) for the year.?

The Defense Ministry said the increase is due to the “Chinese Communists' continued expansion of targeted military activities in recent years, the normalization of their harassment of Taiwan's nearby waters and airspace with warships and war planes”.

(With AP inputs)