Dubai (Platts)--6May2013/1143 am EDT/1543 GMT

The US Navy and 40 allies gathered in Bahrain Monday to begin two weeks of naval anti-mine exercises designed to keep the Persian Gulf open to oil shipping.

Although the exercises, billed as the largest ever in the region, have been scheduled for some time, they are taking place against the backdrop of threats by Iran to shut the Strait of Hormuz oil chokepoint at the mouth of the Persian Gulf if attacked and coincide with rising tensions over developments in Syria, Iran's primary ally in the Middle East.

"International Mine Countermeasures Exercise 13, May 6-30 is the largest exercise of its kind in the region and will exercise a wide spectrum of defensive operations designed to protect international commerce and trade; mine countermeasures, maritime security operations and maritime infrastructure protection," the US naval command in Bahrain said in a statement.

"We are very pleased to see that more than 40 nations have joined us here to take part in this opportunity to enhance international naval capability to preserve freedom of navigation in international waterways," said Vice Admiral John Miller, commander of the US 5th Fleet headquartered in Bahrain.

"If 41 nations are willing to come here and practice [mine countermeasures], just imagine how effective the global mine response would be if someone actually put mines in the water," he added.

Staff from the participating nations, which Arab media reports said included some Gulf Arab states, have started arriving in Bahrain for the onshore phase of the exercises ahead of the maritime drills scheduled to begin next week and will involve 35 ships, 18 unmanned underwater vehicles and more than 100 explosive ordinance disposal divers.

The exercises will cover "surface mine countermeasures, mine hunting and airborne mine countermeasures operations, international explosive ordnance disposal training, diving operations, small-boat exercises, unmanned aerial vehicle operations, unmanned underwater vehicle operations and port clearance operations," the statement said.

Representatives from the maritime shipping industry also will be involved in the drills and conduct an oil spill response discussion during the exercise, it added.

The maritime infrastructure protection part of the exercise "focuses on protecting maritime points of origin and arrival, such as ports or offshore terminals. This portion of the exercise will include shore and harbor security operations, visit, board, search and seizure teams and specialized aircraft," the statement said.

The Persian Gulf region is home to 60% of the world's conventional crude oil reserves and several of the world's largest oil producing nations rely on Gulf ports to export crude oil to the global market, including OPEC heavyweight Saudi Arabia.

Kuwait, Qatar and Iran rely exclusively on their Persian Gulf ports to export crude. Saudi Arabia, which is now producing more than 9 million b/d, has the option of using its Red Sea ports to export oil and has in recent months re-directed more crude to its Western ports as Iran reiterated threats to shut down the Strait of Hormuz.

Iraq exports a large proportion of its crude oil through the Persian Gulf but has the option to ship oil through its northern pipeline system to Turkey while the UAE recently completed a 1.5 million b/d pipeline to the port of Fujairah outside the Strait of Hormuz.

Roughly 20% of the world's tradable oil transits the narrow strait on its way to world markets.

Iran, which is facing pressure from the world's powers to end its controversial uranium enrichment program, has said that it would shut the strait if it came under attack from either the US or Israel, neither of which have ruled out military action if Tehran refuses to comply. Iran has denied it is developing atomic weapons though it has yet to agree to halt uranium enrichment at a secret site despite several rounds of nuclear talks with the big powers in the past year.

--Kate Dourian, kate_dourian@platts.com; Edited by Jeff Barber, jeff_barber@platts.com

© 2013 Platts, The McGraw-Hill Companies Inc. All rights reserved.  To subscribe or visit go to:  http://www.platts.com

http://www.platts.com/RSSFeedDetailedNews/RSSFeed/Shipping/21011621