Israeli defense minister Benny Gantz said on Saturday his "initial assessment" was that Iran was responsible for an explosion on an Israeli-owned ship in the Gulf of Oman.

"Iran is looking to hit Israeli infrastructure and Israeli citizens," Gantz told the public broadcaster Kan. "The location of the ship in relative close proximity to Iran raises the notion, the assessment, that it is the Iranians."

"Right now, at an initial assessment level, given the proximity and the context - that is my assessment," Gantz said, adding that a deeper investigation still had to be carried out.

The ship, a vehicle-carrier named MV Helios Ray, suffered an explosion in the Gulf of Oman between Thursday and Friday morning. A US defence official in Washington said the blast had left holes above the waterline in both sides of the hull. The cause was not immediately clear and no casualties were reported.

The ship is owned by a Tel Aviv company called Ray Shipping through a company registered in the Isle of Man, according to a UN shipping database.

Kan named the owner as Rami Ungar and quoted him on Friday as saying: "The damage is two holes, diameter approximately 1.5 metres, but it is not yet clear to us if this was caused by missile fire or mines that were attached to the ship."

Tensions have risen in the Gulf region since the United States reimposed sanctions on Iran in 2018 after then-president Donald Trump withdrew Washington from a 2015 nuclear deal between Iran and major powers.

Washington has blamed Iran for a number of attacks on shipping in strategic Gulf waters, notably on four vessels, including two Saudi oil tankers, in May 2019. Iran has denied carrying out those attacks.