Under that deal, first mooted in 2007, Saudi Arabia will get 85 Boeing F-15S combat jets, upgrades on 70 already in Saudi service, helicopters, missiles and tanks.
The sale, the biggest arms deal in U.S. history, will lock Riyadh into a relationship with Washington for at least 20 years, easing strains caused by 9/11.
The United States is the world's leading arms supplier and the Saudi deal will reportedly support 75,000 jobs, major defense firms like Boeing, Lockheed Martin, Northrop Grumman and General Electric have said.
Middle Eastern sources said the Saudis offered to expand that deal when U.S. Secretary of Defense Robert Gates visited Riyadh April 6.
Two days later, the U.S. Navy said the Saudi Ministry of Defense and Aviation had asked for price lists on surface warships with integrated air and missile defenses, helicopters, patrol craft and base infrastructure.
This is a key element in Riyadh's program known as Saudi Naval Expansion Program II, worth as much as $23 billion over 10 years.
The Saudi move toward further U.S. arms sales underlines Riyadh's alarm at what it sees as Iranian expansionism amid the pro-democracy uprisings shaking Arab regimes, including the Saudi monarchy.
Saudi Arabia's March 14 military intervention in neighboring Bahrain to support the ruling al-Khalifa dynasty, a close ally, against Shiite-led moves to topple the Sunni monarchy was seen by Iran, which has long claimed the island kingdom, as a direct challenge.
On Monday, Tehran upped the ante and warned Saudi Arabia, Iran's decades-old rival as the paramount power in the Persian Gulf, by cautioning Riyadh of the dire consequences of its unprecedented military deployment.
That was the first time the Iranians have issued such a direct warning concerning an invasion of the kingdom, considered the heart of the Sunni branch of Islam, and marks an escalation of the confrontation by Tehran.
"The presence and attitude of Saudi Arabia (in Bahrain) sets an incorrect precedent for similar events in the future and Saudi Arabia should consider this fact that one day the very same event may recur in Saudi Arabia itself and Saudi Arabia may come under invasion for the very same excuse," declared Iranian Maj. Gen. Yahya Rahim Safavi.
He is a former commander of the elite Islamic Revolutionary Guards Corps and a military adviser to Ayatollah Ali Khamenei, Iran's supreme leader. So the warning carries immense weight.
The Saudi intervention in Bahrain, however it was dressed up as a move by the six-nation Gulf Cooperation Council, peeved the Americans, who had finally got around to endorsing the pro-democracy uprisings against Arab regimes that had long aligned with Washington.
Gates flew to Riyadh seeking to patch things up with King Abdallah, and concluded that there was indeed "evidence" of Iranian interference in Bahrain.
This fitted neatly into Riyadh's allegations of Iranian efforts to stir up Sunni-Shiite animosity in a centuries-old religious schism and to usurp the Sunni states of the region.
The Americans' abandonment of Hosni Mubarak in Egypt, leading to his resignation as president, alarmed Riyadh. It feared that signaled Washington might ditch the Saudis too one day.
"This growing sense of isolation prompted the Saudi leadership to invoke its ultimate reserves of influence in Washington -- the Pentagon," Indian analyst M. K. Bhadrakumar noted in Asia Times Online.
"The promise Abdallah made to Gates -- that Saudi arms purchases from the U.S. this year will exceed the $60 billion deal -- changes the entire complexion of Persian Gulf security from the American perspective."
Bhadrakumar, a former ambassador to the Soviet Union, Kuwait and others, maintained that a "long-standing objective of the Saudi national security strategy remains … to exercise its quasi-hegemony in the Arabian Peninsula."
To do this, the GCC, created in 1981, would be replaced by a "gulf confederation" with a common security and defense policy under Saudi leadership, he wrote.
"If the gulf confederation idea takes hold, the sky's the limit for lucrative arms deals since a joint military will be created by the petrodollar states involving land, air and naval forces."