The Trump administration does not have congressional authorization to go to war against Iran, the Democratic leader of the U.S. House of Representatives said on Thursday amid escalating tensions in the region.

U.S. House Speaker Nancy Pelosi told reporters that the Republican administration would provide a classified briefing for top lawmakers -- the so-called Gang of Eight -- on Iran later on Thursday.

Saudi Arabia's deputy defence minister on Thursday accused Iran of ordering an attack on Saudi oil pumping stations that Yemen'sIran-aligned Houthi militia has claimed responsibility for.

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The attack "proves that these militias are merely a tool that Iran's regime uses to implement its expansionist agenda," tweeted Prince Khalid bin Salman, a son of King Salman.

"The terrorist acts, ordered by the regime in Tehran, and carried out by the Houthis, are tightening the noose around the ongoing political efforts."

The attacks took place against a backdrop of U.S.-Iranian tension following Washington’s decision this month to try to cut Tehran's oil exports to zero and beef up its military presence in the Gulf in response to what it called Iranian threats.

Saudi Arabia and the UAE back the sanctions against Iran, a fellow OPEC producer but regional foe.

Tehran has called the U.S. military presence "a target" rather than a threat, and said it would not allow its oil exports to be halted.

Iran's foreign minister has said “extremist individuals” in the U.S. government were pursuing dangerous policies and Tehran is not seeking confrontation.

After a meeting on Thursday, Kuwait's parliament chief said ministers had discussed preparations for any potential state of war, and he called the coming period "dangerous" and "uncertain".

The Houthis, which have been battling a Saudi-led military coalition for four years, said they carried out Tuesday's drone strikes against the East-West pipeline, which caused a fire but Riyadh said did not disrupt output or exports.

Saudi Arabia's main English newspaper called for "surgical strikes" against Iran.

"Our point of view is that they must be hit hard," said an Arab News editorial. "We call for a decisive, punitive reaction to what happened so that Iran knows that every single move they make will have consequences."

The coalition, which receives arms and intelligence from Western nations, carried out air strikes on Thursday in and around Yemen's capital Sanaa, which the Houthis control.

The drone attack happened two days after four vessels, including two Saudi oil tankers, were damaged by sabotage off the coast of the United Arab Emirates. The other ships were a Norwegian-registered oil products tanker and a UAE-flagged bunker barge.

The UAE has not blamed anyone for that incident, which is being investigated and from which Iran has distanced itself.