WASHINGTON (AP) -- U.S. defense officials say U.S. Navy ships will begin accompanying U.S.-flagged commercial ships when they transit the Strait of Hormuz.

The move is in response to what Washington views as provocative Iranian behavior in the Persian Gulf. Earlier this week Iranian naval vessels reportedly fired warning shots near a Marshall Islands-flagged cargo ship and have detained it and its crew. Iranian officials say the Maersk shipping line owes it money.

Iranian naval patrol boats also surrounded a U.S. cargo vessel in the Strait Friday.

The Navy makes a distinction between accompanying ships and escorting them. The officials said the Navy won't escort these ships but will let them know in advance that they will monitor the situation as they transit the narrow Strait from the Persian Gulf toward the Arabian Sea.

By The Associated Press