The company surprised auction participants by offering winning bids of $56 million and $89 million on two offshore blocks in the Santos basin, where it already has operating wells.

Bradford, Pa., has agreed to buy the Atlantic Richfield Company's interest in six offshore blocks in the Gulf of Mexico for more than $40 million.

After the Eni bid, Sinopec, a Chinese state-owned company, and Sonangol jointly offered $2.2 billion for two other offshore blocks.

Mr. Aiyar's ministry will begin a campaign on Tuesday to promote the auction of 20 onshore and offshore blocks of land for oil exploration.

After securing financing, Cobalt spent about $35 million on 30 offshore blocks in the Gulf of Mexico; it expects to drill its first well next year.

India's ONGC has already invested $12m to explore an offshore block in the region, that it is now drilling.

An additional 13 ultra-deep offshore blocks were demarcated in 2011 and planned for auction.

It participates in 39 offshore blocks in the North Sea and West of the Shetlands.

The most important of these permitted US-based Amoco to prospect in ten offshore blocks between Ada and the western border with Togo.

If Congress does not block the plan, the administration intends to begin leasing offshore blocks to development in December.