U.S President Donald Trump is threatening to hit Iranian cultural sites if Iran retaliates for last week’s assassination of its top general Qassem Soleimani.

The Iranian government has issued a statement announcing its decision to take the fifth and final step in reducing its commitments under the 2015 nuclear deal it signed with world powers, which is officially known as the Joint Comprehensive Plan of Action (JCPOA).

“Turkey’s interference in the region creates a fertile environment for extremists and terrorist groups,” said the Observatory for Monitoring Takfiri Fatwas and Extremist Ideologies at Dar al-Ifta in a statement on Sunday.

A Lebanese Hezbollah official said the response of the Iran-backed “axis of resistance” to the killing of Iran’s military commander Qassem Soleimani in a U.S. air strike will be decisive, al-Mayadeen TV said on Saturday.

Terrorist group ISIS will likely be the winner as tensions between Washington and Tehran mount after the U.S. killing of Iran’s most powerful military commander, experts say.

The American assassination of a top Iranian commander may make it impossible for American forces to stay in Iraq. That could ease an ISIS comeback.

The United States plans to designate an Iranian-backed Iraqi militia as a foreign terrorist organization, the State Department said on Friday, accusing the Asaib Ahl al-Haq group of being a violent proxy of Tehran.

Millions of Iranians took part in the massive funeral of Lieutenant-General Qasem Soleimani and his martyred companions in Tehran.

Hundreds of thousands packed the streets of Iranian holy city of Mashhad to pay tribute to assassinated Lt. Gen. Qassem Soleimani and his companions, who were killed in a US drone strike in Iraq’s Baghdad early Friday.