Jan 1 (Reuters) - India"s Reliance Industries Ltd (RELI.NS) said it plans to raise up to $5 billion in dollar-denominated debt and use proceeds primarily to refinance its existing borrowings. The Mukesh Ambani-owned oil-to-telecoms conglomerate said that the proposal for fixed rate notes, which could be issued in one or more tranches, was approved by the board in a meeting on Saturday. While the company did not give further details on the use of proceeds, the Economic Times newspaper said it will be used refinance earlier debt raised from international investors, with a bundle of loans coming up for maturities in the next three to four months. The newspaper said the offering would be the largest offshore raising by an Indian borrower in one go, adding that the move will be debt-neutral to the company.