New Delhi, May 27 (IANS): Prime Minister Manmohan Singh left for Japan and Thailand Monday morning on a five-day visit during which he will attend a bilateral summit with Japanese counterpart Shinzo Abe and also meet his Thailand's premier Yingluck Shinawatra.

His first stop will be Tokyo. Civil nuclear cooperation talks will be high on the agenda during the three-day visit.

Economic and regional and international issues will also figure high in the talks. Discussions on the Delhi-Mumbai Industrial Corridor (DMIC) and the high-speed train are likely to be held.

Besides, India is likely to seek Japanese investment in various projects, officials said.

The prime minister, who will be accompanied by National Security Advisor Shivshankar Menon and senior officials, will also hold talks on energy cooperation, including on frozen seabed gas hydrates, a breakthrough in Japan that India is interested in.

The bilateral summit was originally slated to be held November last year but was postponed after Japan decided to go in for elections.

"We have been discussing a civil nuclear cooperation agreement and hope to make more progress by end of this year," Foreign Secretary Ranjan Mathai said earlier.

The prime minister is also to address Japanese businesspersons, where he will "highlight major opportunities in India and seek greater Japanese private sector investment in India", said the foreign secretary.

After concluding his Japan visit, the prime minister will also go to Thailand on May 30-31 from where he will return home.

India and Thailand are likely to sign an extradition treaty during the visit.