Saudi Arabia has asked the United States to show restraint in responding to attacks by Yemen’s Houthis against ships in the Red Sea, two sources familiar with Saudi thinking said, as Riyadh seeks to contain spillover from the Hamas-Israel war.

The Iran-aligned Houthis have waded into the conflict that has spread around the Middle East since war erupted on Oct. 7, attacking vessels in vital shipping lanes and firing drones and missiles at Israel itself.

The group which rules much of Yemen says its attacks are a show of support for the Palestinians and has vowed they will continue until Israel stops its offensive on the Gaza Strip – more than 1,000 miles from their seat of power in Sanaa.

The Houthis are one of several groups in the Iran-aligned “Axis of Resistance” which have been attacking Israeli and U.S. targets since the start of the conflict on Oct. 7, when their Palestinian ally Hamas sparked the war by attacking Israel.

Their role has added to the conflict’s regional risks, threatening sea lanes through which much of the world’s oil is shipped, and worrying states on the Red Sea as Houthi rockets and drones fly towards Israel.

Riyadh, the world’s top oil exporter, has watched with alarm as Houthi missiles have been fired over its territory.

The Houthis have emerged as a major military force in the Arabian Peninsula, with tens of thousands of fighters and a huge arsenal of ballistic missiles and armed drones, Reuters reported.

Senior sources in the Iran-aligned camp told Reuters the Houthi attacks were part of an effort to put pressure on Washington to get Israel to halt the Gaza offensive, a goal that Iran shares with Saudi Arabia and other countries in the region.

One of the sources, who is based in Tehran, said Houthi representatives had discussed their attacks with Iranian officials during a meeting in Tehran in November, agreeing to carry out actions in a “controlled” way that would help force an end to the Gaza war. The source was briefed on the matter.

Another of the sources said Tehran did not seek “all-out war in the region” that would risk drawing it in directly.

A Houthi spokesperson did not respond to a request for comment. Iran has denied being involved in the attacks. Iranian officials did not respond to a request for comment on the Houthi attacks.