US isn't upset when its allies mercilessly BOMB babies in Yemen, said Mohammad Javad Zarif.

The US is "in denial" over attacks on oil installations in Saudi Arabia, Iran's top diplomat said Tuesday, after Washington blamed weekend strikes on Tehran despite Yemeni rebels claiming responsibility.

"US is in denial if it thinks that Yemeni victims of 4.5 yrs of the worst war crimes wouldn't do all to strike back," Foreign Minister Mohammad Javad Zarif wrote on Twitter.

American ally Saudi Arabia leads a military coalition that has been battling the Iran-aligned Huthi rebels since 2015.

"The US isn't upset when its allies mercilessly BOMB babies in Yemen for over 4 years-with its arms and its military assistance," Mohammad Javad Zarif said.

"But it is terribly upset when the victims react the only way they can -- against the aggressor's OIL refineries."

The Huthis claimed responsibility for the attack, which halved oil output in Saudi Arabia, the world's top crude exporter.

But on Tuesday, a US official told AFP the strike was launched from Iranian soil and those cruise missiles were involved.

US Vice President Mike Pence said Secretary of State Mike Pompeo would travel to Saudi Arabia on Tuesday to "discuss our response".