U.S. M1A2 "Abrams" tank fires during U.S. led joint military exercise "Noble Partner 2016" near Vaziani, Georgia, May 18, 2016. REUTERS/David Mdzinarishvili/File Photo

The U.S. State Department has approved the potential sale of more than 130 Abrams battle tanks, 20 armored recovery vehicles and other equipment, worth about $1.15 billion, to Saudi Arabia, the Pentagon said on Tuesday.

The approval for land force equipment comes at a time when Saudi Arabia is leading a military coalition in support of Yemeni forces loyal to the exiled government of President Abd-Rabbu Mansour Hadi who are trying to oust Iran-allied Houthi forces from the capital, Sanaa. The coalition’s air strikes have come under criticism from rights groups for the deaths of civilians.

The U.S. Defense Security Cooperation Agency, which oversees foreign arms sales, said that General Dynamics will be the principal contractor for the sale, adding it would contribute to U.S. national security by improving the security of a regional partner.

“This sale will increase the Royal Saudi Land Force’s (RSLF) interoperability with U.S. forces and conveys U.S. commitment to Saudi Arabia’s security and armed forces modernization,” the agency said in a notice to lawmakers posted on its website.

Lawmakers have 30 days to block the sale, although such action is rare.

Saudi Arabia and its mostly Gulf Arab allies intervened in Yemen’s civil war in March 2015 after the Houthi movement had pushed the Hadi administration into exile in Saudi Arabia.

On Tuesday the Saudi-led military coalition conducted air strikes on Sanaa for the first time in five months, residents said, after U.N.-backed peace talks to end the conflict broke down over the weekend.