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WASHINGTON, May 4 (Reuters) - U.S. Navy warships have begun accompanying British-flagged commercial vessels through the Strait of Hormuz as a result of Iran's detention of a Marshall Islands-flagged cargo ship last week, the Pentagon said on Monday.

Army Colonel Steve Warren, a Pentagon spokesman, said the U.S. Navy had accompanied one British ship through the strait, one of the world's most important oil shipping channels, following talks between Washington and London.

"They've asked if we would accompany their flagged vessels through the strait," Warren told reporters.

The Navy has been accompanying U.S.-flagged ships traversing the strait for several days in response to last week's detention of the MV Maersk Tigris by Iranian Revolutionary Guard patrol boats. Pentagon officials say the action is a temporary one as a result of recent Iranian actions in the waterway.

The Maersk Tigris was approached by Iranian patrol vessels last Tuesday and ordered into Iranian waters. The ship's master initially declined and an Iranian vessel fired shots across its bow and forced it to divert to near Larak Island off the port of Bandar Abbas.

The Maersk Tigris remains there as a result of what Iranian officials have said is a court order based on a commercial dispute.

The incident comes at a time of heightened tensions in the region as a result of the conflict in Yemen between Iranian-backed rebels and the Saudi-backed government. The United States is supporting the Saudi-led coalition.

U.S. officials said the Navy began accompanying U.S.-flagged vessels in the strait in part because Iranian patrol boats had shadowed a U.S.-flagged commercial ship going through the vital waterway a few days before the Maersk Tigris was detained.

(Reporting by David Alexander and Phil Stewrat; Editing by Susan Heavey)