The United Nations Security Council had previously found Tehran to be in violation of its commitments under the 2015 agreement and voted to reinstate sanctions, which had been eased in exchange for limiting its nuclear program.
The UN sanctions against Iran came into force on Saturday at midnight.
Prior to this, the UN Security Council on Friday voted on a resolution proposed by Russia and China to delay the reinstatement of sanctions against Iran for six months.
For the resolution to pass in the 15-member UN Security Council, it required at least nine votes in favor and no veto from Britain, France, and the United States.
In the end, the Russia-China proposal was supported by only four countries (Russia, China, Pakistan, Algeria), nine countries opposed it, and two abstained.
