Dhaka: Seven international oil companies have submitted bids for 15 offshore blocks as energy starved Bangladesh looks for potential gas deposits in the Bay of Bengal amid dwelling reserves exposing the economy to growing risks.

In response to the South-Asian country's first offshore bidding round launched two months ago, the foreign oil companies offered to invest $1.6 billion for 16 out of 28 blocks offered for the exploration as the state-run Petrobangla on Wednesday opened the tender documents.

Petrobangla announced the offshore bidding round in February with 20 deep sea blocks and eight shallow water blocks, each comprising 3,000 to 7,000 square kilometres.

"Twenty-five companies have purchased our promotional package and seven of them submitted bids. We are satisfied with the outcome," a Petrobangla spoke-sman told the Gulf News.

Top bidder

Santos International of Australia appeared as the top bidder, making a total investment proposal of $852 million under three Production Sharing Contracts for six blocks in partnership with British Cairn Energy - if it is selected.

US-based company Conoco Phillips submitted four bids for eight deep sea blocks as it intends to sign four production sharing contracts, each for two blocks.

A US-China joint venture, Longwoods Resources, has submitted a bid for one shallow sea block and two deep sea blocks.

Energy experts earlier called this round of bidding "crucial" for Bangladesh's energy sector as the country desperately needs to find new gas reserves as the gas crisis is projected to be acute after 2011.