Iran's proxy says it hit a ship with Saudi military equipment in the Red Sea, as tensions over the US-Iran war remain high.
The Houthis say they launched missiles and drones at "Saudi military build-ups" in the central provinces of Marib and Hadramawt.
US military says it disabled a tanker that was attempting to evade the American blockade on Iranian ports.
It comes as Iran condemned the US plan to use frozen Iranian assets to pay for war damages.
The Iran-backed group in Yemen has threatened to target Saudi vessels in a vital shipping route.
The Iran-backed group, which previously announced a "maritime embargo" against Saudi Arabia, also claims to have hit another vessel.
All of the ships were travelling to or from Saudi ports before changing course, ship-tracking data shows.
The Houthis say the embargo begins immediately and is a response to a Saudi blockade of ports and airports in Yemen.
The Iran-backed Houthis blame Saudi Arabia for the attack in Yemen's capital and say they targeted Abha airport in response.
