Policing the Gulf

The USS Cole carries a crew of 350

The destroyer USS Cole is serving as part of the US Fifth Fleet and had been due to head to the Gulf to help monitor Iraq's compliance with UN sanctions when an explosion holed it in Aden.

Correspondents say what US officials have called a suicide attack represents the most serious incident involving a US warship since an Iraqi jet fired two missiles at the USS Stark in the Gulf in 1987.

Naval officers often board tugs

A US-led multi-national interdiction force (MIF) has been patrolling the Gulf since August 1990, after Iraq invaded Kuwait.

Under a UN embargo established that year, Iraq is prohibited from selling oil except under UN supervision as part of an oil-for-food plan.

But dozens of small ships attempt to run the UN blockade and find willing customers in the region for their cheap oil - especially given the current high prices of oil on the international market.

Containment policy

It has been estimated that the traffic is worth hundreds of millions of dollars a year and Iraqi opposition groups claim that the revenue helps Iraqi President Saddam Hussein support his elite military and intelligence apparatus.

In April, a US destroyer seized a Russian tanker suspected of carrying Iraqi oil in breach of the sanctions - although Moscow denied that the oil was from Iraq.

The US has also repeatedly accused Iran of allowing ships to use its territorial waters.

US warships lead the patrols monitoring sanctions compliance

At the time, the US Defence Secretary William Cohen threatened to step up interception operations in an attempt to maintain containment policy against Iraq.

But commentators say the operation has remained at a constant level.

According to the commander of the US Fifth Fleet, Charles W Moore, more than 29,586 ships have been queried by MIF, of which 12,831 have been borded and 727 diverted.

The Fifth Fleet, which is based in Bahrain, oversees MIF operations.

Hormuz

Its regional engagements also comprise working with members of the Gulf Cooperation Council (GCC) on security and defence, enforcing the no-fly zones over Iraq (Operation Southern Watch) and conducting military exercises with regional allies.

It consists of a carrier battle group, an amphibious ready group, destroyers, frigates and logistic support ships.

But the fleet's priority is to maintain the Strait of Hormuz as a navigable waterway. The strait is one of the most important waterways in the world, with 44% of the oil consumed daily by the world passing through it.

Cracks in sanction policy

Illegal crude oil from Iraq is reported to be shipped across the straits to countries such as the United Arab Emirates, and then sold on to a range of customers, including some in India and Pakistan.

Earlier this year, the UN said oil smuggling through the Gulf was running at record levels. If this continued., the UN said, the total for the year 2000 could reach 4.8m tonnes.

In previous weeks, there have been signs of cracks appearing in the embargo on Iraq.

In September, Russia and France - both permanent members of the UN Security Council - sent civilian aircraft to Iraq. And shortly afterwards, Jordan sent a plane - the first state-sponsored Arab flight since the sanctions were imposed.