Abbas Mousavi, spokesman for Iran's Foreign Ministry, gives a press conference in the capital Tehran on May 28, 2019. (ATTA KENARE / AFP)

DUBAI - Iran dismissed as “illegitimate” efforts by the United States to extend the UN Security Council arms embargo on Tehran, an Iranian Foreign Ministry spokesman said on Monday.

“Iran is not seeking to exit the 2015 nuclear deal with six powers ... America’s move is illegitimate and our reaction will be proportionate,” Abbas Mousavi said in a televised weekly news conference.

President Donald Trump’s administration has been taking a harder line with the United Nations over its desire to extend and strengthen the embargo on Iran

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The United States said on Thursday it was “hopeful” the UN Security Council would extend the arms embargo on Iran before it expires in October.

President Donald Trump’s administration has been taking a harder line with the United Nations over its desire to extend and strengthen the embargo on Iran.

Washington has threatened to trigger a return of all UN sanctions on Iran as leverage to get backing from the 15-member Security Council on extending the UN arms embargo on Tehran.

“The United States is not a member of the nuclear deal anymore ... Iran’s reaction to America’s illegal measures will be firm,” Mousavi said.

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Trump withdrew the United States from the Iran nuclear deal in 2018 and reimposed sanctions on Tehran that have crippled its economy.

Under the deal, Iran agreed to halt its sensitive nuclear work in exchange for sanctions relief.

Iran, which denies its nuclear program is aimed at building a bomb, has gradually rolled back its commitments under the accord since the United States quit. It argues that Washington’s actions justify such a course.