United National Party (UNP) leader Ranil Wickremesinghe was sworn in as the Prime Minister of Sri Lanka on Sunday, ending a 51-day power tussle in the island nation that had crippled the government. The UNP leader had refused to step down asserting that his sacking was illegal.

Wickremesinghe, 69, was administered the oath of office by President Maithripala Sirisena, who had sacked him on October 26 in a controversial move which plunged the island nation into an unprecedented constitutional crisis.

Wickremesinghe's re-appointment comes a day after former strongman Mahinda Rajapaksa, who was installed as Prime Minister by President Sirisena, resigned Saturday, after two crucial Supreme Court decisions made his efforts to cling to premiership untenable.

According to media reports, a new Cabinet will be sworn in on Monday. The Cabinet will consist of 30 members and include six Sri Lanka Freedom Party (SLFP) parliamentarians.