Colombo: Sri Lanka’s powerful Rajapaksa brothers secured a landslide victory in the parliamentary election, giving them the two-thirds majority of seats required to make constitutional changes, according to results released Friday.

Prime Minister Mahinda Rajapaksa is likely to be sworn in the same position by his younger brother, President Gotabaya Rajapaksa, after the vote that could strengthen dynastic rule in the Indian Ocean island nation.

“Sri Lanka People’s Front has secured a resounding victory according to official results released so far,” Gotabaya Rajapaksa said in a Twitter message as results were being released. “It is by belief that that the expectation to have a Parliament that will enable the implementation of my ‘vision for prosperity’ policy will be reality tomorrow,” he said.

The Rajapaksas’ Sri Lanka People’s Front won 145 seats in the 225-member Parliament while its main opponent obtained only 54 seats, the election commission’s results showed. A party representing ethnic minority Tamils won 10 seats, and 16 others were split among 12 small parties.

The brothers need 150 seats, or control of two-thirds of seats in Parliament, to be able to change the constitution. At least four small parties collaborate with Rajapaksas’ party, so they appear to have mustered that support.

However, analysts say any attempt by Gotabaya Rajapaksa to push for changes that will strengthen presidential power at the expense of those of the prime minister may trigger sibling rivalry.

Sri Lanka had been ruled by powerful executive presidents since 1978. But a 2015 constitutional amendment strengthened Parliament and the prime minister and put independent commissions in charge of judiciary appointments, police, public services and the conduct of elections.

Gotabaya was elected president last November after projecting himself as the only leader who could secure the country after the Islamic State-inspired bombings of churches and hotels on Easter Sunday that killed 269 people. Since being elected, he has said he had to function under many restrictions because of the constitutional changes.

However, Mahinda Rajapaksa is unlikely to cede any of his powers that might shrink his influence as he works on promoting his son Namal as his heir. Namal and three other members of the Rajapaksa family contested the election and are likely to control key functions in the new administration.

The landslide victory also raises fears of weakening government institutions such as independent commissions for elections, police and public service.

More than 70% of the country’s more than 16 million eligible voters cast ballots in Wednesday’s election, held under strict health guidelines to prevent the spread of the coronavirus.

The vote was postponed twice by the pandemic. Sri Lanka has largely contained the spread of the virus with 2,839 confirmed cases, including 11 deaths.

The United States congratulated Sri Lanka for holding the election “in a peaceful and orderly manner despite the challenges posed by the COVID-19 pandemic.”

“As the new parliament convenes, we hope the government will renew its commitments to building an inclusive economic recovery, upholding human rights and the rule of law, and protecting the country’s sovereignty. We look forward to partnering with the government and new parliament,” the U.S. Embassy in Colombo said in a statement.