The government and LIC together hold 60.72% of IDBI Bank.
That stake is to be sold to a subsidiary of Fairfax Financial Holdings for about Rs 52,878 crore.
Management control would pass to the buyer.
Employees fear for service conditions, pensions and reservations.
They began a two-day hunger strike on November 2.
The strike is against the planned strategic sale of IDBI Bank, and reports say more than 10,000 employees across branches and offices are expected to take part.
IDBI Bank told the stock exchanges on October 31 that it had received the strike notice, according to The Sunday Guardian.
The buyer is a subsidiary of Canada-based Fairfax Financial Holdings, identified in coverage as 10955230 Canada Inc.
The sale covers a 60.72% stake, made up of the combined holdings of the government and LIC, for about Rs 52,878 crore, according to The Sunday Guardian.
Management control would pass to the buyer, and the Union Cabinet has approved the strategic sale, according to the same report.
The forum has demanded that the privatisation and strategic sale be withdrawn.
It has also asked that the government keep at least 51% ownership of the bank.
Other demands include protecting existing service conditions and welfare benefits, safeguarding pension and retirement benefits, and continuing reservation policies and industry-level wage revisions.
The forum also wants protection for contractual and outsourced workers and has asked for written assurances on employee rights if ownership changes.
Reports say the forum has also demanded absorption of around 15,000 outsourced and contractual workers.
The forum wants employees to have an option to move to public sector banks while keeping their service records, seniority, pay scales and retirement benefits.
The forum has warned it could intensify its agitation, including a prolonged or indefinite strike, if the demands are not met.
The Joint Platform of Central Trade Unions has urged a halt to the disinvestment and called for an independent investigation and a Parliamentary review, according to reports.
IDBI Bank branch, Paravur (file image), Wikimedia Commons, CC BY-SA 3.0
