New Delhi, Aug 30 (ANI): Prime Minister Narendra Modi is on his way to Japan on Saturday for a five-day trip, hoping to win Japanese backing for a nuclear energy pact and lure investment to help kick-start its economy. Accoring to experts, getting a nuclear deal will be Modi's top priority during the visit. Defence expert Uday Bhaskar, however said that Modi will have to first address Japan's concern about nuclear proliferation. Japan wants explicit guarantees from India, which has not signed the international Nuclear Non-Proliferation Treaty, to ensure that spent fuel is not diverted to make bombs.