Lawyers for President Uhuru Kenyatta and his Deputy William Ruto were on Saturday holed up in Nairobi as they pored over the petition filed at the Supreme Court by Nasa leaders Raila Odinga and Kalonzo Musyoka.
Sources indicated that top Jubilee Party officials had also joined the lawyers as they worked round the clock to prepare a comprehensive defence.
The petition, which was filed on Friday night, comprises 24 pages with annexures and affidavits totalling 25,000.
The Sunday Nation learned that Jubilee has deployed all its resources to ensure that they have a water-tight reply to the petition.
The party's Secretary-General Raphael Tuju said its team of lawyers was studying the petition but added that they will only reply to what affects them.
"We're looking at the petition. But you realise it is IEBC (Independent Electoral and Boundaries Commission) that declared the results and, therefore, our response will only be in relevant areas," he said.
He declined to say how many lawyers the party had at its disposal. "We have a controlled system and we only release information on need be basis," he said.
Mr Tuju said Jubilee will accept whatever outcome the Supreme Court will render in less than a fortnight.
"They tell us they won the presidency but circumstantial evidence shows us otherwise. We have the majority in Parliament and also majority governors," he said.
Elgeyo-Marakwet Senator Kipchumba Murkomen, in his Twitter account, appeared to dismiss the petition predicting a win for Jubilee.
"I have read Nasa's petition and their prayers. There is nothing to worry about. The truth will set us free.
"Once again the win of President Uhuru and DP Ruto will be confirmed by the Supreme Court," he said.
Lawyer Ahmednasir Abdullahi, one of the lawyers who represented the electoral commission during the 2013 presidential election petition, wrote on Twitter that there was nothing worrying about the petition.
Some of the issues Jubilee lawyers will be seeking to reply to from the petition include allegations of numerous instances in which votes were deducted from Mr Odinga and added to President Kenyatta.
NASA: Uhuru votes were inflated
The chairman of the electoral commission, Mr Wafula Chebukati, said President Kenyatta had garnered 8,203,290 votes (54.2 per cent) against Mr Odinga's 6,762,224 votes.
An affidavit by Dr Nyangasi Onduwo, who works as an economic adviser for Mombasa Governor Hassan Joho, says he examined over 25,000 vote declaration forms and detected errors in 14,000 of them.
Other documents state that the votes cast in the presidential election (15,588,038) exceeded those for governors (15,098,646) and members of the National Assembly (15,008,818) by 482,202 and 567,517 ballots respectively.
Nasa also says the commission flouted the rules of managing the election.