State-run IDBI Bank today said it has firmed up plans to raise up to $ 300 million through a medium-term Swiss franc bond issue.

"It (bond issue size) would be between $ 250-300 million ... We have finished the road shows and will be deciding on details like the exact amount and timing in the next 2-3 days," IDBI Bank Chairman and Managing Director R M Malla told reporters on the sidelines of a function here.

The funds raised through the bonds will be used for lending to Indian corporate clients for their ECB (external commercial borrowings) through its branch in the Dubai International Finance Centre, he said.

The bonds will hold a five-year maturity and the bank is expecting to raise the money at 200 basis points over Swiss Franc mid swaps, Executive Director Melwyn Rego said.

He said the lender will be looking at retail investors to raise the money rather than the conventional practice of tapping institutions which are targeted in such issues.

IDBI Bank has done road shows in Zurich, Geneva and Lugano over the past few weeks for creating awareness among potential investors, he said.

The bank today inaugurated a special safe deposit vault facility at its headquarters in the Cuffe Parade, south Mumbai, which will be open round the clock.

Malla, who christened the facility as ATL (all time lockers), claimed this makes the bank the first institution in the world to offer a 24-hour vault facility.

It will have special security features under which a customer can only get a biometric-based access to the facility while iris scan will be added soon, he said.