The requested sale of 1,000-pound (450-kilogram) bomb casings, worth an estimated $151.8 million, was approved by the State Department's Bureau of Political-Military Affairs, according to a press release.

"The proposed sale will improve Israel's capability to meet current and future threats, strengthen its homeland defense, and serve as a deterrent to regional threats," the bureau said in a statement.

In addition to the munitions, the sale will include US government and contract engineering, logistics and technical support services, according to the release.

Major US defense companies have agreed to quadruple production of advanced weapons, President Donald Trump said in a social media post Friday, a week after the US and Israel first launched strikes on Iran.

While US arms sales typically require approval by Congress, Secretary of State Marco Rubio has issued a waiver bypassing the approval, to the consternation of some elected officials.

"The Secretary of State has determined and provided detailed justification that an emergency exists that requires the immediate sale to the Government of Israel of the above defense articles and defense services is in the national security interests of the United States," the State Department said, citing the Arms Export Control Act.

Congressman Gregory Meeks, a Democrat on the House Foreign Affairs Committee, said bypassing congressional review of the arms sale "exposes a stark contradiction at the heart of this administration's case for war."

"The Trump administration has repeatedly insisted it was fully prepared for this war," Meeks said in a statement. "Rushing to invoke emergency authority to circumvent Congress tells a different story."

"This is an emergency of the Trump administration's own creation."