Russia's state arms exporter is launching a big drive at the Tripoli air show to sell combat jets, missiles and air-defense systems to Middle Eastern states, including the state-of-the-art S-400 Triumf surface-to-air missile that Iran and Syria desperately want to acquire.

But the Russians are likely to find considerable competition at the 4th Arab-African Aviation Exhibition and Conference, known as LAVEX-2009, in the Libyan capital that opened Monday.

The four-day arms fair is likely to attract major international defense companies that are falling over themselves to upgrade Libya's long-neglected military as well as supply the Middle East, the largest arms market in the developing world.

But the Russian arms exporter, Rosoboronexport, will also find keen interest in its wares by the Libyan government.

The Libyan leader, Col. Moammar Gadhafi, is miffed that he has not had the access to U.S. arms companies he had expected after he abandoned his clandestine nuclear arms program in 2003 in a high-profile gesture of reconciliation with the international community following decades of isolation.

U.N. trade sanctions that blocked U.S. and Western companies from dealing with Libya were not lifted until 2004, and Washington did not restore full diplomatic relations with Tripoli -- and remove it from its terrorism blacklist -- until 2006.

In the meantime, Gadhafi has turned to Russia and France for his arms requirements.

Gadhafi, who last month marked his 40th year in power, also angered the United States by securing the Aug. 20 release from a Scottish prison of a former intelligence agent convicted for the 1988 bombing of a Pan Am jumbo jet over Scotland that killed 270 people.

The Libyan leader was harshly criticized for giving the former agent, Abdelbaset Ali al-Megrahi, a rapturous hero's welcome when he arrived back in Tripoli aboard a presidential jet.

For Gadhafi, Megrahi's release on compassionate grounds -- he has terminal cancer -- gave him a powerful platform to demonstrate his ability to defy the West and win domestic and regional plaudits.

So the Russians may find considerable interest in their weapons systems, at a time when Moscow is driving to boost its ailing defense industry and to regain the influence it had in the Middle East and North Africa during the Cold War.

Algeria, Syria, Yemen and Sudan were key defense clients until the collapse of communism in 1991. Iran, once a U.S. ally, is now an important purchaser of Russians arms, and Arab states, even U.S.-oriented Saudi Arabia, are showing interest in Russians weapons systems.

The reason behind the interest being shown by the Saudis, who have reputedly offered Moscow to buy arms worth $2 billion, is primarily political rather than military.

Riyadh wants to use that inducement to persuade Russian not to sell Iran advanced air-defense systems that would protect its controversial nuclear sites.

The Russians say they are confident that these deals will go through, but if the United States and Iran can find a diplomatic solution to the nuclear issue, Riyadh may not be so keen to go ahead with such arms deals.

Still, Moscow has delivered arms worth $2.5 billion to the United Arab Emirates and $1 billion to Kuwait in recent years.

Rosoboronexport officials say regional states have shown interest in Russian arms, including the twin-engined Sukhoi Su-35 fighter. It's equipped with weapons systems capable of engaging several air targets simultaneously.

It also carries the new Irbis-E radar, which allows the pilot to detect and track up to 30 air targets while engaging eight of them at one time with its 30mm cannon and eight tons of missiles.

Moscow hopes to export at least 160 Su-35s to Algeria and other countries. Such exports are vital for keeping Russian production lines going to supply Russia's military forces.

But all eyes are likely to be on the S-400 Triumf -- NATO designation SA-21 Growler -- which can intercept and destroy at a range of up to 250 miles and engage six targets at once.

Iran and Syria want advanced air-defense systems to protect their strategic installations against possible U.S. or Israeli attacks, largely aimed at destroying Iran's nuclear facilities.

But U.S. and Israeli pressure on Moscow has so far blocked the sale of the S-300 system, forerunner of the S-400, which would make any airstrikes far more costly than they would be at this time.