Japan will observe for now the current developments in the Iranian nuclear standoff and put off any decision on whether to impose sanctions before a meeting next week between Iranian and European negotiators, Foreign Minister Taro Aso said Friday.

"I would like to refrain from making any comment when matters are unpredictable," Aso told a news conference, referring to the possibility that Japan could impose economic sanctions against Iran.

Calling the Iranian response made Aug. 22 "clearly unsatisfactory" and falling short of the U.N. demands, Aso said, "There are different directions we can take" in line with a provision of a U.N. Security Council resolution on the Iranian nuclear issue.