TEHRAN, Aug. 10 -- The moment Iran's parliament first threatened to close the Strait of Hormuz, it was read as a warning, the kind that deters without the cost of enforcement. On Sunday, lawmakers moved to make it something else.

Iran's National Security and Foreign Policy Commission approved a bill that would ban American and Israeli vessels from transiting Hormuz and the Persian Gulf, and impose fines of up to 20 percent of cargo value on ships carrying goods with Israeli commercial or military affiliations. The vote, reported by the Islamic Republic of Iran Broadcasting, advances the measure to a full parliamentary session, where a majority of the 290-seat legislature would need to ratify it.

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