India's Adani Green Energy is likely to raise $500 million by issuing dollar bonds in March, two officials aware of the plans said, making it the first Adani group company to return to the overseas bond market in a year.

"The company is doing the groundwork and talking to investors to get a sense on pricing," said a foreign banker, who is a part of the discussions.

"Once there's more clarity on pricing and demand, they will finalise the details and tap the market," the banker said.

Part of Indian billionaire Gautam Adani's ports-to-power conglomerate, Adani Green is likely to use some of the proceeds from the proposed bond issue to refinance existing debt that will mature this year, the officials said.

Both the officials and the banker spoke on condition of anonymity as they are not authorised to speak to the media.

Adani Group did not respond to Reuters' e-mail seeking comment.

A report by U.S. short seller Hindenburg Research in January last year had led to a sell-off in stocks and overseas listed bonds of Adani group companies, forcing them to retreat from the foreign currency bond market and buyback $315 million of listed overseas debt securities.

Since then, most of the group's foreign bonds are back above the levels they traded at before the Hindenburg report, giving the company comfort to look at a fresh issue of dollar bonds.

Adani Green Energy conducted non-deal roadshows in January and reached out to investors in Hong Kong and Singapore. It will soon start roadshows for the proposed bond issue, the officials said without elaborating on the timing.

The company is in talks with foreign banks and investors and is yet to appoint arrangers for this issue, the banker said.

"The spreads for Adani Group's dollar bonds have definitely come down from last year, so the deal should get reasonably priced," according to the banker.

Adani Green Energy recently completed the funding to redeem its $750 million bonds due in September, eight months before they mature.

On Tuesday, Moody's revised Adani Green's rating outlook to "stable" from "negative" considering the company's improved financial flexibility and reduced refinancing risk after the repayment of senior notes.

The rating agency also affirmed Adani Green's Ba3 rating, which reflects predictable cash flow backed by long-term power purchase agreements and high financial leverage.

Among other Adani group companies, Adani Transmission may also tap the overseas bond market this year, according to merchant bankers. (Reporting by Bhakti Tambe; Editing by Sonia Cheema)