Orders placed by host nation the United Arab Emirates at the IDEX defence show topped four billion dollars on Tuesday as the arms fair prospered despite the global credit crunch.

The oil-rich UAE, determined to maintain its defensive capabilities despite the plunging value of its main source of income, stepped up spending by ordering military air transporters in two mega deals together worth 2.9 billion dollars.

Other contracts took the total value of outlays announced by the UAE armed forces on Tuesday to 12.3 billion dirhams or 3.35 billion dollars, spokesman General Obeid al-Ketbi said at a press conference.

The giant orders, including some deals for provision of services as well as equipment purchases, followed spending of 3 billion dirhams or 812 million on Monday by UAE buyers.

Nearly 900 exhibitors from 50 countries are taking part in the show which has doubled in size since the last time it was held, in 2007, with extra features including a newly-dredged area of quay for warships and naval craft.

The biennial fair takes place amid a global economic slowdown which has triggered a massive drop in oil prices, hitting the buying power of oil-rich Gulf Arab states, which are traditionally big spenders on weapons.

But Ketbi has dismissed fears of the global financial crisis reducing spending during the show.

"I believe that this IDEX show will be stronger than all previous editions… I do not expect the purchase volumes to be impacted by the global economic crisis," he said.

The military transport plane order is split between US manufacturers Boeing and Lockheed Martin, with Boeing being asked to supply four C-17 air transporters for 4.8 billion dirhams (1.3 billion dollars), Ketbi said.

Lockheed Martin will furnish the UAE armed forces with 12 of its C-130J design for 5.9 billion dirhams (1.6 billion dollars).

Ketbi said local leasing and financing firm Al-Waha Capital has been instructed to arrange finance for the two contracts, which are part of a plan to modernise the armed forces' fleet.

"These are final deals," he said.

Lockheed Martin's regional vice president for international business development, Rick Groesch, who at was the press conference, appeared surprised by the announcements.

"No, we have not signed the deal," he said, adding that the company he represents is still in discussions with al-Waha Capital to finalise the order.

He added, however: "We are in final discussions about the aircraft."

Among other deals, Ketbi announced the award of a 459.4-million-dirham (125.2-million-dollar) contract to Germany's Rheinmetall Defence Electronics to build a combat training centre for the UAE armed forces.

Local company Advanced Integrated Systems was awarded two contracts to provide the armed forces with machines and programmes worth a total of 432.7 million dirhams (118 million dollars), he said.

The UAE's Critical National Infrastructure Authority, which is responisble for protecting all vital facilities in oil-rich Abu Dhabi, has awarded the Abu Dhabi Ship Building company (ADSB) a contract worth 460 million dirhams (125.3 million dollars) to build a fleet of new fast interceptor vessels.

Also, the Abu Dhabi investment arm Mubadala Development has reportedly signed a Heads of Agreements (HOA) with Sikorsky Aerospace Services, paving the way for a joint venture establishing an aviation military maintenance repair and overhaul (MRO) center in Abu Dhabi.

No details were available of defence purchases by other countries.

In IDEX 2007, the UAE announced orders worth 918.2 million dollars compared to 1.85 billion dollars worth of military equipment ordered in the 2005 edition of the show. IDEX was launched in 1993.