The ruling BJP had swept the by-elections, winning 12 of the total of 15 seats
Karnataka Chief Minister BS Yediyurappa on Friday said the the ministry expansion was likely to take place after December 20 or 22 after discussions with the party high command.
"It maybe late by eight to 10 days. We will expand the cabinet and those promised will be inducted into the Ministry there is no confusion on that," Mr Yediyurappa told reporters.
Mr Yediyurappa said he has been asked to go to Delhi after a week to discuss the expansion exercise as BJP National President Amit Shah was busy with the Jharkhand assembly polls and other matters.
"I have already spoken to him. The cabinet expansion will be done after December 20 or 22," he added.
After his government retained majority in the Assembly by sweeping the December 5 bypolls, Mr Yediyurappa had recently said that he would soon leave for Delhi to hold discussions with the BJP central leadership on cabinet expansion.
The ruling BJP had swept the by-elections, winning 12 of the total of 15 seats, helping the four-month-old Yediyurappa government retain majority in the Assembly.
However, there is talk within BJP circles that Ministry expansion may get further delayed as Dhanurmasa (considered an inauspicious month among Hindus) will begin on December 16 and will end with Makar Sankranti in the third week of January.
Meanwhile, lobbying has intensified for ministerial berths, by both BJP old guard and new entrants.
Mr Yediyurappa has made it clear that 11 disqualified MLAs (of the total 13 fielded by BJP) who successfully contested the bypolls on party tickets, will be made Ministers.
Cabinet expansion will not be an easy task as Mr Yediyurappa will have to strike a balance by accommodating the victorious disqualified legislators as he had promised and also make place for the old guards, upset at being "neglected" in the first round of the induction exercise.
He also has to give adequate representation to various castes and regions in his cabinet, that currently has 18 ministers, including the Chief Minister and the sanctioned strength is 34.