State-run IDBI Bank today hit the overseas debt market with a benchmark-sized five-year bond issue to raise over USD 500 million, according to merchant banking sources.

"IDBI Bank is raising over USD 500 million through a five-year Reg S (Regulation S bonds) note issue. The five-year bond issue, maturing in January 2019, has an initial pricing guidance of 315 basis points over the US treasury bills," a merchant banker involved with the sale of the senior unsecured notes programme told PTI.

The current issue is part of the bank's USD 3.5 billion medium-term notes programme.

Meanwhile, global rating agency Standard & Poor's has assigned BBB- rating to the proposed IDBI issue, S&P said in a statement issued from Singapore.

S&P further said the rating on the notes reflects the long-term counter party credit rating on the issuer.

The notes will constitute direct, unconditional, unsecured and unsubordinated obligations of IDBI, the rating agency added.

It can be noted that more and more domestic companies are accessing overseas markets for funding as the rupee funds are too costly.

So far in 2013, over half a dozen companies, including RIL, PowerGrid, Tata Com, ICICI Bank, HDFC Bank, Exim Bank, and Bharti Airtel among others, raised USD 4.25 billion from overseas debt market.