In an interview with the BBC broadcast on Thursday, Obama said the military option is still on the table even after the landmark diplomatic achievement earlier this month over Tehran’s nuclear program.

“We are settling the Iran deal, but we still have a big account that we’re going to have to work. Hopefully some of it diplomatically, if necessary some of it militarily,” the US president said.

Obama acknowledged that Iran was funding its strategic priorities even during the sanctions and economic hardship.

“Iran has shown itself to be willing, even in the midst of real hardship, to fund what they consider to be strategic priorities,” he noted.

Obama said US Persian Gulf allies that have worries about the situation in the Middle East should strengthen their militaries and address social and political issues that are leading to the threat of the ISIL terror group.

Regarding the release of Iran’s frozen assets, he said this was part of the nuclear deal.

Obama’s remarks come after Iran and the P5+1 group of countries reached a conclusion on the Joint Comprehensive Plan of Action (JCPOA) on July 14 in the Austrian capital of Vienna following days of intensive talks over Tehran’s nuclear program.

Senior Republican lawmakers have vowed to do their best effort to scuttle the Iran nuclear pact.

Republicans control majorities in both chambers of Congress. Many have strongly opposed the agreement, which they say will threaten US ally Israel and empower Iran.

Secretary of State John Kerry and Secretary of Energy Ernest Moniz offered a vigorous defense of the Iran agreement as they faced tough questioning at a Senate committee hearing on Thursday.