The United States announced new sanctions against Iran on Tuesday over its ballistic missile programme and what it called Tehran's support for terrorist groups in the Middle East.

The sanctions announced by the State Department target 18 individuals or entities described as supporting Iran's ballistic missile programme or the elite Republican Guard.

The announcement came a day after the United States certified that Iran was complying with the landmark nuclear deal signed two years ago with the United States and other world powers, but also warned it was preparing new sanctions.

“The United States remains deeply concerned about Iran's malign activities across the Middle East which undermine regional stability, security, and prosperity,” State Department said.

It cited Iran's support for Hezbollah, Hamas, the regime of Syrian President Bashar al-Assad and Huthi rebels in Yemen fighting a US-backed coalition led by Saudi Arabia.