Iranian President Hassan Rouhani said he favors talks and diplomacy but not under current conditions, state news agency IRNA said late on Monday.

“Today’s situation is not suitable for talks and our choice is resistance only” IRNA quoted Rouhani as saying.

US President Donald Trump said earlier on Monday that Iran would be met with “great force” if it attempted anything against US interests in the Middle East, adding that Tehran has been very hostile toward Washington.

I think Iran would be making a very big mistake if they did anything,” Trump told reporters as he left the White House on Monday evening for an event in Pennsylvania. “If they do something, it will be met with great force but we have no indication that they will.”

His comments came as two US government sources said the United States strongly suspects Shi’ite militias with ties to, and possibly encouragement from, Iran fired a rocket on Sunday into Baghdad’s heavily fortified Green Zone.

The sources, who are familiar with US national security assessments and spoke on condition of anonymity, said the United States was still trying to establish which militia fired the Katyusha rocket on Sunday and the extent, if any, of Iranian involvement.

The rocket fell in the Green Zone which houses government buildings and embassies and caused no casualties, the latest in a series of regional attacks the United States believes may have been inspired by Iran. 

Iran has rejected allegations of its possible involvement in attacks last week and Iran’s Iraqi allies rushed to condemn Sunday’s rocket blast.