Repsol, struggling under the weight of its debt in a country heading for a European bailout, launched in July the sale of the LNG interests, which includes a 75 percent stake in a regasification plant in Canada, a 20 percent stake in a liquefaction plant in Peru and a 23 percent interest in the Atlantic liquefaction plant in Trinidad and Tobago.

"There's plenty of interest in the assets. Repsol has asked for combined offers for the three assets rather than separately because there could be problems with clauses on changes over control," one of the sources said.

Repsol has not provided an official valuation of the LNG interests but in a presentation in August said they had off-balance sheet debt of 3.6 billion euros ($4.6 billion) and gross debt of 1 billion euros.

The Spanish group wants to cut net debt by 7 billion euros to 9 billion over the next four years and sell about 4.5 billion of asset sales to preserve its investment grade rating and fund a planned 19.1 billion euros of investments.

The sources tipped China's Sinopec, Spain's Gas Natural , Britain's BG Group, Novatek and Gazprom of Russia and France's GDF Suez - which could bid with China's sovereign wealth fund CIC - as the companies that have presented bids.

Repsol declined to comment, as did Gas Natural, BG Group, GDF, Gazprom and Novatek. Sinopec was not immediately available for comment.

Separately, GAIL (India) Ltd confirmed that it was also interested in the assets as it looks for additional LNG supplies to meet rapidly growing demand.