Bengaluru : Senior Congress leader and former Karnataka chief minister SM Krishna resigned from the party on Saturday.

The 85-year-old leader conveyed his decision to quit from the Congress Working Committee (CWC) in a letter submitted to party president Sonia Gandhi.

Taken aback by his move, the Congress leadership has deputed party general secretary BK Hariprasad, who hails from Karnataka, to persuade the veteran leader to take back the resignation.

It is not clear what prompted the former Union minister for external affairs to take such a decision. Krishna was not available for comment. However, he has called a press conference on Sunday, where he is expected to speak about his decision.

Congress sources said Krishna was feeling “suffocated” in the party for a long time. Though inducted into the CWC, he was not given any important organisational role either at the national level or in the state. He hardly attended meetings of the party’s highest decision making body.

Krishna led the Congress to victory in the state in 1999 and served as the chief minister till 2004. He was instrumental in making Bengaluru the IT capital of the country.

He first became a member of parliament (MP) in 1968 from Mandya. He also served as the governor of Maharashtra for the period 2004-2008.