Both Washington's European allies and Tehran pledged on Tuesday to uphold the 2015 Iran nuclear deal despite President Donald Trump's decision to pull the United States out and reimpose sanctions.

European leaders decried Trump's decision to withdraw from the deal, which had lifted sanctions against Iran in return for curbs on its nuclear program. They called on Washington not to take steps that would prevent other countries from upholding it.

Iran's President Hassan Rouhani said Tehran aimed to continue to comply with the deal's terms and would swiftly reach out to the other signatories — Britain, France, Germany, Russia and China — to keep it in place.