Japan is closely following the situation after Iran suspended some commitments under an international nuclear deal and will use Tokyo's amicable ties with Tehran to ensure peace and stability in the Middle East, a government spokesman said Wednesday.

"We hope to use our traditionally friendly relations with Iran to solve problems through dialogue and achieve peace and stability in the region," Chief Cabinet Secretary Yoshihide Suga said, adding that Iran playing a "constructive" role is important.

"The Iranian government's decision is not to withdraw from the nuclear agreement and we take note of this point, the top government spokesman said at a press conference. "We will continue to monitor the situation carefully."

Iranian President Hassan Rouhani said Wednesday that Tehran plans to keep more enriched uranium than allowed under the 2015 nuclear deal with world powers, threatening to start higher uranium enrichment if no progress is made in negotiations with other parties within 60 days.

Rouhani added, however, that Iran does not plan to leave the nuclear deal, a year after U.S. President Donald Trump decided to pull the United States out of it.

Under the deal reached between Iran and six powers -- Britain, China, France, Germany, Russia and the United States -- the Islamic republic agreed to curb its nuclear activities in exchange for the lifting of economic sanctions.

Japan, a nonmember, has supported the deal intended to strengthen the nuclear nonproliferation regime. But the recent hardening of stance by the United States has put its security ally Japan in a difficult position as Tokyo seeks to maintain good relations with Tehran.

The United States reinstated sanctions it had lifted under the nuclear deal, and ended waivers granted to buyers of Iranian oil, including Japan, to cut off Tehran's oil revenue last week.

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