Nairobi — The United States military could deploy armoured divisions within days of an order to attack Iraq, using huge seaborne arsenals already within striking distance of the Gulf, naval and defence experts said last week.

The United States Army and United States Marine Corps will immediately be able to call on 17 military ships packed with tanks, assorted heavy armour and ammunition strategically placed near the British naval base of Diego Garcia in the Indian Ocean.

At a top speed of 24 knots the ships can steam within sight of Iraqi shores some 4,500 km away in five or six days. At 20 knots the vessels can cover 500 miles a day.

The United States and its allies took six months after Iraq's invasion of Kuwait in August 1990, to build up sufficient firepower in the region before launching the Desert Storm ground war in February 1991.

"It will be different this time," Military Sealift Command's public affairs director, Marge Holtz, told Reuters.

"There is more pre-positioned equipment afloat - we learnt a lot from the Gulf War." Military Sealift Command (MSC) is the branch of the United States Navy charged with transporting armour and military supplies for the United States armed forces.

Akin to floating armouries, eight of the 17 vessels are newly-built Watson-class military ships. At more than 275 meters long and 100 feet wide they are not far short of the dimensions of New York's Empire State Building.

Each has a hold capacity of 380,000 square feet (35,300sq metres), equivalent to eight soccer fields.

"With these immense ships, the United States' sealift capability has been hugely enhanced since the Gulf War," said Joanna Kidd a naval defence analyst with the International Institute for Strategic Studies (IISS) in London.

"They can not carry troops but then the troops can be flown in," she said. The eight Watson-class ships make up Afloat Pre-positioning Squadron Four, strategically positioned equipment for the United States Army covering the Gulf and the Indian Ocean, MSC said.

"The ships laden with army equipment at (Diego) Garcia support a heavy United States Army brigade of up to 3,500 troops," she said.

Daubed in a military grey livery, the vessels can each carry 58 Abrams battle tanks, 48 other track vehicles such as Bradley fighting vehicles and 900 other trucks, according to MSC. Of the remaining nine vessels, six stationed at Diego Garcia are part of Maritime Prepositioning Ship Squadron Two and have enough equipment to support 17,300 marines for 30 days, MSC's Holtz said.

Slightly smaller at 600 feet in length, they are also loaded with tanks, ammunition and general military supplies. Details of a further three vessels operated by MSC were not available.

The seaborne equipment is in addition to materiel already at United States bases in the Gulf sufficient to supply at least one division, according to ground forces expert Phillip Mitchell of the IISS.

The United States President George W Bush and British Prime Minister Tony Blair are determined nothing should go wrong with this war.

It is a war inspired entirely an ant-Saddam Hussein logic. The United States and Britain have not learnt to trust the Iraqi leader.

A United States division is made up of approximately 17,000 troops while a brigade is up to 4,000 men, depending on whether it is light or heavy infantry.

The ability to carry Abrams tanks, one of the heaviest tanks in the world and the backbone of the United States Army, would be vital to any significant land-based assault were it needed, military experts said.

The largest transport aircraft of the United States Air Force can manage just one Abrams tank. John Reinhart, chief executive of Maersk Line, a United States subsidiary of Danish shipping giant, Maersk Sealand, which operates 15 of the ships on behalf of the military, told Reuters they would be crucial in any significant land attack scenario.

"I think what this (use of pre-positioned ships) does is bring that much more stuff closer to a potential area, though I imagine there will still be a need to charter some (extra) ships on the open market ," he said.

Since August, the MSC has chartered at least four merchant vessels to carry helicopters, tanks, and ammunition from the United States east coast and bases in Europe to the Gulf and the Red Sea.

Those ships have carried much smaller loads, with the last carrying 72,000 square feet of equipment, and appear to be incremental shipments.

Because of their size, the massive pre-positioned ships need deep-water ports, such as those found in Saudi Arabia and Kuwait, to accommodate them.

The military can call on a further 16 similar transport vessels, now moored at United States ports and packed with armoury and ready for action.

The fastest of these, seven Fast Sealift Ships (FSS) capable of sustained speeds of 30 knots (720 miles a day), could be in the Gulf, 8,000 miles away, in just under two weeks.

The seven FSS ships can carry enough equipment and supplies to support close to a full mechanised division, MSC says.

The remaining ships that are part of the so-called surge fleet and also loaded with armour are as large as the biggest vessels deployed around Diego Garcia and would be used to transport rolling stock for heavy combat divisions.

They would take just over two weeks to reach the Gulf.

In a protracted campaign, MSC would be able to draw on an additional fleet of 62 vessels, including troop-carrying ships and general cargo ships, in the Ready Reserve Force maintained by contractors under the United States.

Maritime Administration in a state of four-day, five-day, 10-day and 20-day readiness.