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.

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.

Saudi Arabia is one of the top buyers of weapons in the developing world.