India has embarked on a project to build a 'concept demonstrator' of an unmanned underwater vehicle in 30 months, Scientific Adviser to Defence Minister Dr V K Aatre said on Thursday.

"It is very difficult to put a timeframe for a project like this... We want to put something in water and see whether we can have an autonomous (unmanned) underwater vehicle without any sensors," Dr Aatre told mediapersons in Bangalore.

Defence Research Development Organisation, he said, had begun work on the concept demonstrator for initial trials.

Aatre said India was lagging behind the United States in technology, but was even with other countries.

Earlier, delivering the 19th Brahm Prakash memorial lecture on 'Ocean Marine Acoustics and Underwater Technologies' at the Indian Institute of Science, he said the country had indigenous capability to build all types of SONARs.

"We are self reliant in the technology except for chips... India has built all type of SONARs," Aatre said.