Raytheon and Lockheed Martin have become key elements in an accelerating drive by Saudi Arabia and its Persian Gulf partners to build an integrated missile defense shield to protect the energy producers against Iran's growing missile arsenal.

On Jan. 2, the Raytheon Co. of Massachusetts announced a $582.5 million contract to supply the United Arab Emirates, a regional military heavyweight, with AN/TPY-2 radars for the Terminal High Altitude Area Defense missile defense system, or THAAD.

The seven-emirate federation is the first foreign buyer of THAAD, for which Lockheed Martin is the prime contractor.

Under a $3.48 billion deal announced in Washington Dec. 25, the emirates acquired two units with 96 interceptor missiles.

The missiles are produced at its Troy, Ala., facility. The AN/TPY-2 X-band radars will be manufactured at Raytheon's plant in Massachusetts.

Two years ago, the Americans deployed one of their AN-TPY-2 units in Israel's Negev desert south of Tel Aviv to bolster Israeli missile defenses with the capability to detect Iranian ballistic missiles at long range. But the unit remains under U.S. control.

Discussions are under way for a THAAD sale to Saudi Arabia. Washington is also urging the kingdom to upgrade its 16 Patriot Advanced Capability-2 batteries, which have 96 missiles, to PAC-3 standard.

Raytheon announced Jan. 4 that it had completed its first Configuration-3 Patriot radar upgrade for Kuwait's military, the first of six such upgrades for the northern gulf emirate which has 40 PAC-2 Patriots.

The Saudis are also contemplating the purchase of DDG- 51 Arleigh Burke-class Aegis destroyers that could be armed with ballistic missile defense capability.

These would be the most powerful vessels in the Saudi navy, whose main surface combatants are currently French destroyers and frigates.

The U.S. Navy's 9,100-ton DDG 51s form the backbone of its BMD force and one of these vessels is always deployed in the gulf.

The kingdom is reported to be considering the purchase of up to a dozen new warships worth between $20 billion-$23 billion under Naval Expansion Program II.

Apart from U.S. moves to maintain cutting-edge defenses against Iran in the region, Washington has long pressed the gulf monarchies to upgrade and strengthen their missiles defenses.

The six member states of the Gulf Cooperation Council -- Saudi Arabia, the United Arab Emirates, Kuwait, Qatar, Oman and Bahrain -- have paid lip service to the concept of an integrated early warning system linked to a missile defense shield for two decades.

But progress has varied from patchy to negligible over the years, largely because of traditional dynastic rivalries and a reluctance by the smaller states to put their forces under the control of Saudi Arabia, the major power on the Arab shore of the gulf.

"One factor holding back GCC defense integration has been Saudi Arabia's unwillingness to sanction collective security arrangements that might weaken the GCC as a Saudi-led defense treaty," Oxford Analytica noted in a Nov. 11 analysis.

"This factor appears to be receding, with Riyadh appearing confident that it remains the bloc's military leader."

The attitude of the other GCC states has changed quite dramatically in the last few years as they came to grips with the harsh reality of Iran's buildup of ballistic and medium-range missile arsenal that presents a multi-layered threat to the Arab states.

The Americans started building up their anti-missile defenses in the gulf during the administration of President George W. Bush.

These included U.S. Navy ship-borne systems and land-based systems in four of the GCC states -- the emirates, Qatar, Bahrain and Kuwait. These mainly comprised two batteries each of Raytheon Patriot missiles capable of intercepting short-range missiles.

Saudi Arabia and the emirates purchased U.S. weapons systems, including missile defense systems, worth around $15 billion in 2007-2009.

"The GCC already feels confident that it can intercept Iranian combat aircraft," Oxford Analytica observed. "The next step is to reduce the damage from potential cruise and ballistic missile attacks.

"The United States provides early warning systems and maintains an outer screen of missile interceptors on naval vessels in the gulf.

"Saudi Arabia, the United Arab Emirates and Kuwait have accelerated their plans to field their own ship-based outer layer of defense and to procure long-range, land-based interceptors such as THAAD, as well as to modernize and reinforce short-range land-based interceptors such as the Patriot."