US officials have confirmed they intend to sell $60bn (£38bn) of arms to Saudi Arabia, including helicopters and jets.
The state department said details of the deal had been sent to Congress, which now has 30 days to object.
If completed, it could be the most lucrative single arms deal in US history and could support 75,000 jobs.
The state department said Israel, traditionally wary of arms deals involving Arab states, was not expected to raise objections.
Announcing the plan, state department official Andrew Shapiro said it had a "tremendous significance from a strategic regional perspective".
"It will send a strong message to countries in the region that we are committed to support the security of our key partners and allies in the Arabian Gulf and broader Middle East," he said.
Analysts say the sale - which includes more than 80 F-15 fighters, and dozens of Apache, Black Hawk and Little Bird helicopters - is unlikely to face much opposition in Congress.
The plan was leaked last month, when officials were quoted as saying anti-radar missiles, precision-guided bombs, and Hellfire missiles would also be included.
But officials did not mention the missiles during Wednesday's news conference.
The Pentagon said the Saudis were expected to initially select about $30bn worth of aircraft. Delivery of the weapons is expected to be spread over 15 to 20 years.
Saudi Arabia is one of the top buyers of weapons in the developing world.