Japan [Images] may not give any immediate commitment to support the Indo-US civilian nuclear deal, a senior official said in Tokyo on Friday ahead of the talks between Prime Minister Manmohan Singh [Images] and his Japanese counterpart Shinzo Abe [Images].

Japan will wait for negotiations between India and the International Atomic Energy Agency to see New Delhi's 'sincerity' before firming up its position on the issue, he said.

He noted that Japan, considering its relations with India, would trust New Delhi but domestically its national sentiments were very strong since it was the only country to have suffered due to nuclear weapons.

Giving a sense of Japanese position on the issue, which will be raised by Dr Singh during his meeting with Abe, the official said it will be difficult to say 'yes easily' and it will take a long time before Tokyo firms up its position on the issue.

Dr Singh will be seeking Japan's support to India's quest for civil nuclear energy, particularly in the backdrop of recent passage of law in Washington on the Indo-US civil nuclear deal.

"We have a sense of trust when India says it is ready to respond in a responsible manner on the nuclear issue," the official said.

He said Japan feels that India has 'sincere desire' to utilise nuclear energy for peaceful purposes, particularly to generate power.

"But the situation is complex as there are strong national emotions in Japan because it is the only country to have suffered due to use of nuclear weapons. It is difficult to say yes easily on the issue," the official said.

The Indo-US civil nuclear deal is being studied by Japan and it will discuss the issue at the Nuclear Suppliers Group, the official said. Asked whether Japan will suggest any measures for the IAEA to take with regard to India, he said Tokyo did not have specific proposals but was ready to engage New Delhi in talks on the matter.

Japan, whose 40 per cent electricity is generated using nuclear energy, will be ready to cooperate with India after it firms up its position on whether or not New Delhi should receive international cooperation in the field, he added.

When referred to the assertion by Dr Singh in Japanese Diet on Thursday that India was committed to abolition of nuclear weapons universally, the official said: "In the light of Japan's relations with India, that kind of commitment will be seen with trustworthiness."