Swearing-in of four main ministerial portfolios are likely to be held on the same day, sources add.
Earlier reports claimed that Mr. Wickremesinghe's swearing in is likely to get delayed.
Meanwhile, Mahinda Rajapaksa is to resign tomorrow (15) after addressing the nation, UPFA MP Lakshman Yapa Abeywardena told the media following a meeting with president Maithripala Sirisena at the presidential secretariat.
However, president Sirisena is due to attend a ceremony at the Diyatalawa Army camp, delaying Wickremesinghe’s oath-taking, said an official of the president’s office.
UNP expects speedy response
Meanwhile, UNP general secretary Akila Viraj Kariyawasam has told BBC Sinhala Service that he hoped the president would end the political crisis soon by giving the premiership to Wickremesinghe, who commanded a parliamentary majority.
The president has responded positively to that, said Kariyawasam.
Meanwhile, a UNP senior said on condition of anonymity that the president promised to the UNP leader last night to take the next court of action following the Supreme Court hearing of the appeal against the Court of Appeal injunction against Rajapaksa’s premiership today.
He added that they were working to submit a vote on account next week for state expenditure for the next year.
(Last update : 09.45pm Dec. 14, 2018)