Bangladesh's foreign secretary Touhid Hossain summoned Indian High Commissioner Pinak Ranjan Chakravarty and handed over a written protest urging an immediate cessation of survey activities, spokesman Yeakub Ali said.

The complaint came after naval personnel spotted an Indian survey ship and two support vessels late Thursday in territory claimed by Bangladesh in the Bay of Bengal.

Bangladesh says the area in question is part of its deep sea gas block number 14, which analysts say is rich in hydrocarbon.

Crew members on the Bangladesh vessel asked their Indian counterparts to exit the waters but were told they were in their own waters, a foreign ministry statement said.

In a separate written statement, Foreign Minister Iftekhar Ahmed Chowdhury urged New Delhi to 'postpone the survey' until a settlement was reached on the territorial dispute.

'We are confident that peaceful deliberations and diplomatic measures will ultimately lead to a mutually acceptable solution in this regard,' the statement said.

A naval commander told AFP two Bangladeshi ships had been sent to the region and a third was on its way as a reinforcement.

Last month a similar row between Bangladesh and its eastern neighbour Myanmar flared over another disputed stretch in the bay.

Bangladesh deployed four ships and put its navy and armed forces on high alert after a South Korean company escorted by Myanmar ships began work in the area.

A series of top-level diplomatic talks between the two failed to resolve the dispute and it was only after Myanmar removed the ships that it simmered down. -- AFP