COLOMBO, Sri Lanka — President Mathripala Sirisena of Sri Lanka on Saturday suspended Parliament for two weeks as he sought to shore up support for unseating the country’s prime minister, escalating a political crisis.
Mr. Sirisena suspended Parliament after ousting Prime Minister Ranil Wickremesinghe on Friday, a move many lawmakers and government ministers denounced as unconstitutional. Mr. Sirisena swore in as prime minister Mahinda Rajapaksa, a popular former president who was accused of human rights abuses and corruption during a decade in power.
Mr. Wickremesinghe struck a defiant tone, claiming he was still prime minister. “Convene Parliament, and I will prove it,” he said.
By Saturday afternoon, many lawmakers were vowing to stick by Mr. Wickremesinghe, demanding that a formal count be taken in Parliament to determine who held a majority in the house. That’s when Mr. Sirisena announced that he was suspending Parliament. He also dismissed the leaders of several government institutions, replacing them with loyalists.
As of 5 p.m. local time, Mr. Wickremesinghe remained in office at Temple Trees — the official state residence of the prime minister — where he briefed diplomats from the United States, the United Kingdom and more on the political developments.
Addressing a news briefing earlier in the day, he pledged to leave office if it was proved that he did not hold the majority in the house. The dispute could be resolved peacefully in Parliament, and there was no need to plunge the country into political crisis, Mr. Wickremesinghe said.
But frontliners in Mr. Rajapaksa’s party have warned Mr. Wickremesinghe that they will give him until Sunday morning to leave the official prime ministerial residence unless he wanted the public to “force him out.”
To clinch a majority in Parliament, Mr. Sirisena needs to secure just over half of the 225 seats in the house to form a new government with Mr. Rajapaksa’s party. A tally on Saturday suggested they held only 98 seats.
But Namal Rajapaksa, a lawmaker and the son of the former president, said by telephone that the numbers were in their favor.
“Of course we have more than 130 seats in Parliament, definitely,” Namal Rajapaksa said. “We are already working on our policies to stabilize the economy and provide social stability.”
Mr. Sirisena was a cabinet member in Mahinda Rajapaksa’s government until he broke from the ruling party to form a coalition with Mr. Wickremesinghe to contest the 2015 elections, which they won by a slim majority.
In the run-up to elections, the coalition promised to investigate alleged war crimes and corruption during the tenure of Mr. Rajapaksa, who simultaneously served as president and finance minister, among other cabinet positions, while his three brothers served as the defense secretary and ministers of economy and ports.
But those investigations lagged under the unity government. The Rajapaksa family denies any wrongdoing, painting the allegations as lies perpetrated by their political opponents.
Acrimonious divisions ultimately doomed the unity government, which was consumed by bitter infighting between Mr. Sirisena and Mr. Wickremesinghe. Sri Lankans have grown unhappy with the economy stagnating and social unrest breaking out at times, including outbursts of sectarian violence.
Whether Mr. Sirisena will face popular backlash remains to be seen. Mr. Rajapaksa is very popular in the country, but this is the first time since Sri Lanka earned independence from Britain that power has been handed over unconstitutionally, observers say.
“The president has no authority to remove the prime minister,” Jayadeva Uyangoda, a retired university academic and political scientist explained. “The removal of the prime minister is a function of Parliament, unless he resigns.”
Namal Rajapaksa, the son of the former president, remained confident, adding that the majority of Sri Lankans supported the new government because the previous cabinet had failed to govern effectively.
“If you talk to people who voted for the unity government, they all agree that there is not unity in the unity government,” he said. “But now you will have stability with the new government. People can oppose us, but at the end of the day, we will achieve a solution for the economic and social instability.”
Mr. Sirisena’s party may now join with Mr. Rajapaksa’s party, Namal Rajapaksa said, giving the family a good shot at reclaiming power in presidential elections next year.