Taiwan’s main opposition party secured control of the island’s legislature, underscoring the potential challenges ahead for president-elect Lai Ching-te in pursuing major reforms.

A new cohort of legislators were sworn in Thursday after prevailing in January’s election, which returned the US-friendly ruling party to power. Their first job was to elect a speaker, eventually choosing Han Kuo-yu, a former presidential candidate for the Kuomintang, after two rounds of voting.

Securing the speaker’s role gives the KMT effective control of Taiwan’s legislative agenda for the next four years. The opposition’s win represents a headache for the Democratic Progressive Party’s Lai, who will take office in May, making it harder for him to push through policies that require legislative changes.

The KMT favors closer ties with China, which views Taiwan as part of its territory, putting it at odds with the DPP, which holds that the island is a de facto independent nation.

While no party won an outright majority in the 113-person legislature in the recent election, the KMT has the most seats with 52. Lai’s DPP has 51 while the Taiwan People’s Party has eight. There are also two independent lawmakers.

The new speaker is widely seen as a divisive figure in Taiwan. Han won a surprise victory in 2018 to become mayor of Kaohsiung, the southern port city typically viewed as a stronghold of DPP support.

He rode a strong wave of support to challenge outgoing President Tsai Ing-wen in the 2020 election, which she won in a landslide. He was ejected from his position as mayor later that year in a recall vote.