Japan on Tuesday said it was still closely examining the progress on India's civil nuclear deal with the US and will take its own time to decide on the issue.

Briefing reporters after Japanese Foreign Minister Taro Aso's meeting with Prime Minister Manmohan Singh and other leaders attending the SAARC summit, Japan foreign ministry spokesman Mitsua Sakaba said his country will take its own time to arrive at a decision.

During the meeting, Singh requested Japan to extend support to India's peaceful nuclear programme but Japan said it is watching developments related to the Indo-US deal and would arrive at a decision only after it takes some final shape.

Sakaba said it was a matter of "great concern" for Japan that India was still not a signatory to the Non-Proliferation Treaty (NPT). "So Japan will like to have some kind of guarantee that there is no proliferation, which we do not have so far," he said.

At the same time, Japan understood India's need for using nuclear power to meet its energy deficit, he said.

On Pakistan, the spokesman said Tokyo has asked Islamabad to fight the spurt of terrorist activity on the Pakistan- Afghan border and to support Afghanistan in fighting terrorists on the frontier for stability in the region.