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MANAMA, Nov 2 (Reuters) - The U.S. Navy began a series of exercises in the Gulf and wider Gulf waters on Friday involving a U.S aircraft carrier and two expeditionary assault ships.
The five-day crisis response exercise involved amphibious, air and medical forces, the U.S. Navy's Fifth Fleet, headquartered in Bahrain, said in a statement.
"The scenario is challenging but prepares us for a real-world event," Commander Jay Chambers, of Combined Task Force 59, said.
The start of the exercises coincided with world powers agreeing at talks in London to push ahead with a third round of sanctions against Iran, unless reports indicate Tehran has tried to address their concerns about its nuclear programme.
Washington has not ruled out military action against Iran, which lies on the Gulf. Tehran denies it is seeking nuclear weapons.
Fifth Fleet spokesman Lieutenant John Gay said the exercises had been planned for months and were not related to specific events, instead outlining only humanitarian assistance and natural disaster scenarios for the manoeuvres.
"Our primary goal is to enforce maritime security including the free flow of commerce through the Gulf for all regional partners ... We are committed to keeping the Strait of Hormuz open to ensure that there is a free flow of commerce throughout the region," Gay said.
The United States has launched several war games at Iran's dourstep in recent years. In June, the largest U.S. military flotilla to enter the Gulf since the 2003 Iraq war wound up two weeks of war drills off Iran's coast and near the Strait of Hormuz, a major channel for oil shipments from the Gulf.
Iran has dismissed the U.S. naval war games near its waters as a morale boosting exercise for American forces.
An Iranian Revolutionary Guards naval commander suggested on Monday that Iran's Islamic militia forces would be capable of disrupting strategic Gulf oil shipping routes with a small operation if ever the need arose.
Chambers said the manoeuvres were designed to practise a coordinated response to a natural disaster or crisis in the region.
The navy said the exercise inside the Gulf was led by a task force that includes the Wasp, an amphibious assault ship. The vessel, which looks like a small aircraft carrier, carries Marine corps helicopters and landing craft.
The navy also said the aircraft carrier Enterprise and its strike group and the Kearsarge expeditionary strike group had begun training in wider Gulf waters.
The Kearsarge is another amphibious assault ship equipped with helicopters and landing craft. The U.S. Marine Corps operates from the ship, which is designed for rapid deployment.
"Multiple strike groups are capable of executing a broad range of operations," the U.S. Navy said.