TAIPEI (Reuters) - Taiwan on Friday appointed the former chairman of its ruling pro-independence party as premier, after the incumbent resigned along with the entire cabinet, in response to local election defeats.

(L-R) Former premier William Lai, Taiwan President Tsai Ing-wen and new premier Su Tseng-chang join hands after a news conference in Taipei, Taiwan January 11, 2019. REUTERS/Fabian Hamacher

November’s election losses presented a major challenge to President Tsai Ing-wen, who faced mounting criticism at home over her reform agenda while facing renewed threats from China, which considers the self-ruled island its own.

Tsai appointed Su Tseng-chang, a two-term former chairman of her Democratic Progressive Party (DPP), saying Taiwan faced challenges amid rising Chinese threats and trade tension between key backer the United States and China.

“Taiwan’s democracy and development must face certain challenges,” Tsai said, adding that China was looking to force its “one country, two systems” structure on the island.

Su vowed to lead the administration amid the challenges and learn from earlier mistakes.

“The situation is difficult and the task is tough,” he said.

Su’s appointment followed the widely expected resignation of William Lai, the second premier to quit since Tsai took office in 2016, in line with a practice of leaders quitting when their party loses a major election.

“I must resign to take responsibility for the election defeat,” Lai told a cabinet meeting earlier on Friday.

Taiwan’s premier forms the cabinet and runs the government on a day-to-day basis. New ministerial appointments are expected soon.

Just a year ahead of the next presidential election, analysts say Tsai and the new premier must shore up public support for the government’s policy on China ties and further boost the island’s export-reliant economy in a challenging year amid the China-U.S. trade war.

Su was appointed premier in 2006 by former president Chen Shui-bian, who infuriated Beijing and strained Taiwan’s relationship with the United States during his tenure from 2000 to 2008.

Su, nicknamed “light bulb” by his supporters for his bald head, has led Taiwan’s most populous New Taipei City for years. He was defeated by a candidate from the China-friendly opposition Kuomintang in November.

Tsai has said her administration would reflect on the election defeats but would stand firm to defend Taiwan’s democracy in the face of renewed Chinese threats.

Chinese President Xi Jinping, who has stepped up pressure on Taiwan since Tsai became president, threatened this month to use force to bring the island under Beijing’s rule and urged “reunification”.

“The new premier not only has to focus on domestic matters but must also pay much more attention to cross-Strait and national security issues,” Yao Chia-wen, a senior adviser to the president, told Reuters.

He said the new premier must deal with issues such as the prevention of swine fever from China and possible election interference.

Some from within the embattled leader’s party have urged Tsai not to seek re-election. She has not explicitly said whether she would run for president in 2020 but has warned against Chinese efforts to interfere with elections.