Iran's President Hassan Rouhani speaks to officals after his swearing in ceremony in Tehran, on August 5, 2017.
Rouhani warned the US against tearing up the nuclear deal as he was inaugurated for a second term, but he also faces challenges closer to home amid accusations he is rolling over to conservatives. (AFP PHOTO)

TEHRAN, Aug. 8 (Xinhua) -- If the United States violates the 2015 nuclear deal with Iran, it will be the "loser" as Iran will keep all options on the table, Iran's nuclear chief warned on Tuesday.

"The U.S. will be the loser if it goes against the JCPOA," Ali Akbar Salehi, head of the Atomic Energy Organization of Iran (AEOI), was quoted by the state-run news agency IRNA as saying.

JCPOA is short for the Iranian-U.S. nuclear deal formally called the Joint Comprehensive Plan of Action (JCPOA), which was signed last year by the two countries after years of tough negotiations on the controversial Iranian nuclear program.

The deal was signed under the auspices of other world powers, including Britain, China, France and Russia, which are permanent members of the UN Security Council, plus Germany.

Under the deal, the U.S. eased economic sanctions on Iran in exchange for its commitment to peaceful use of nuclear energy.

Tehran will reciprocally respond to Washington's violations of the international deal, Salehi warned in an interview with the Lebanese TV news channel Al Mayadeen.

Washington has to bear responsibility for its actions that violate the nuclear deal, because the International Atomic Energy Agency (IAEA) has verified Iran's peaceful nuclear program by releasing seven reports to confirm Tehran's commitment, Salehi added.

The U.S. administration led by President Donald Trump recently imposed new sanctions on Iran, which were slammed by Tehran as a violation of the nuclear deal.