Prime Minister Manmohan Singh Thursday concluded his three-day visit to Japan. He will arrive in Bangkok later in the afternoon.
The prime minister attended a bilateral summit with his Japanese counterpart Shinzo Abe during the visit.
In Bangkok, he will meet his Thailand counterpart Yingluck Shinawatra.
India and Japan continue to differ on the contentious issue of the Comprehensive Test Ban Treaty (CTBT) even though Japan has assured it would work to prepare the ground for India to become a full member of the international control regimes for nuclear exports.
In a joint statement issued in Tokyo by Manmohan Singh and his Japanese counterpart Shinzo Abe on the "Strengthening of strategic and global partnership" between India and Japan, the CTBT issue continued to be an irritant.
"The two prime ministers reaffirmed their shared commitment to the total elimination of nuclear weapons. Prime Minister Abe stressed the importance of bringing into force the Comprehensive Nuclear-Test-Ban Treaty (CTBT) at an early date. Prime Minister Singh reiterated India's commitment to its unilateral and voluntary moratorium on nuclear explosive testing," the joint statement said.
India, a nuclear weapons state, has refused to sign the CTBT while maintaining that it was committed to a unilateral and voluntary moratorium on nuclear testing.
But Japan offered help India in civil nuclear cooperation.
"Prime Minister Abe recognized India's sound non-proliferation record. Both sides expressed their commitment to continue to work to prepare the ground for India to become a full member in the international export control regimes: the Nuclear Suppliers Group, the Missile Technology Control Regime, the Australia Group and the Wassenaar Arrangement," the statement said.
"The two prime ministers also reaffirmed their commitment to working together for immediate commencement and an early conclusion of negotiations on a non-discriminatory, multilateral and internationally and effectively verifiable Fissile Material Cut-off Treaty (FMCT)," it said.
PM will leave for India from Bangkok Friday morning.