MOSCOW (AP) — Russia's foreign minister says the landmark Iran nuclear deal can be amended only as long as his country and other signatories agree to proposed changes.

President Donald Trump last week threatened to pull the United States out of the deal week unless U.S. lawmakers amend the law that allows and spells out the terms of Washington's participation in the international accord.

Trump alone cannot actually terminate the 2015 agreement, which lifted sanctions that had choked Iran's economy in exchange for Tehran rolling back its nuclear program. But withdrawal by the U.S. would render it virtually meaningless.

Speaking at a conference in Moscow, Russian Foreign Minister Sergey Lavrov said on Friday that any unilateral changes to the deal "could bury this agreement, which is vital for strategic stability and nuclear non-proliferation."