Former Karnataka chief minister BS Yeddyurappa will formally launch his new Karnataka Janata Party (KJP) on Sunday.
The former BJP leader is scheduled to take over as KJP president at a rally in Haveri, around 350km from here.
Yeddyurappa has claimed that more than four lakh people will attend his party´s launch.
It remains to be seen how many BJP ministers and legislators attend the rally, defying expulsion threats by the ruling party.
On Saturday, the BJP government in Karnataka sacked cooperative minister and Yeddyurappa loyalist BJ Puttaswamy for alleged anti-party activities.
Another Yeddyurappa supporter G Basavaraj, a Lok Sabha MP from Tumkur, was suspended from the party.
Chief minister Jagadish Shettar and state BJP chief KS Eshwarappa made the formal announcement about the decision here on Saturday.
Yeddyurappa formally quit the BJP on November 30.
He also resigned from the Karnataka Assembly.
The 70-year-old leader submitted his resignation to Speaker KG Bopaiah at the state secretariat and reportedly asked him to accept it immediately.
On July 31 last year, Yeddyurappa was forced to resign as chief minister of Karnataka after he was indicted by the then Karnataka Lokayukta N. Santosh Hedge in the illegal mining report.
He and his family members were named by Hegde in what was called a Rs 16,000 crore illegal mining scam.
Yeddyurappa walked out of jail on November 8 last year on bail.
The veteran leader is credited to bringing the BJP to power in Karnataka.