Ahead of coming assembly polls due in May, Karnataka BJP chief K.S. Eshwarappa Thursday announced he has resigned from the post.
"I have sent my resignation to the party president Rajnath Singh," he told reporters in Shimoga, his home town, about 270km north of Bangalore.
He said he expected the party to decide on his successor in three or four days.
The resignation came as a surprise though his three-year term as state party president ended in January as there was speculation that the Bharatiya Janata Party (BJP) might retain him in the post till the assembly elections are over.
The party, ruling Karnataka for the first time, is in a bad shape due to corruption scandals and dissidence. Talk in BJP circles was that changing the party chief when assembly polls are near will only worsen the situation in the state unit as there were many aspirants for the chair.
Mr Eshwarappa took over as state party chief in Jan 2010 after resigning from the ministry headed then by B. S. Yeddyurappa.
He joined the Jagadish Shettar cabinet as one of the deputy chief ministers in July last year. Eshwarappa will continue as deputy chief minister handling revenue portfolio.