The Houthis, who are headquartered in Yemen, launched 21 drones and missiles into the southern Red Sea on Tuesday, according to reports from the United States and Britain, which also hinted at potential more actions to safeguard international maritime lines.

As the three-month-long conflict between Israel and Hamas in Gaza continues to spread throughout the Middle East, British Defense Secretary Grant Shapps stated that it was the worst strike the terrorists have carried out in the region yet.

Shapps warned reporters, “This is an unsustainable situation,” and cautioned them to “watch this space” for future action from Britain and its allies.

“This cannot continue and cannot be allowed to continue.” According to U.S. Central Command, there were no reported casualties or damages, and this was the 26th strike by the Houthis on commercial maritime lines in the Red Sea since November 19.

Yahya Saree, a spokesman for the Houthi military, claimed later in the day that militants with Iranian support fired a sizable number of drones, ballistic missiles, and naval missiles at a U.S. ship that was “providing support” to Israel.

Saree said in a televised statement that the action was a “preliminary response” to an earlier U.S. airstrike that claimed the lives of ten Houthi militants. Still, she did not specify the date of the Houthi strike or the extent of any damage the vessel had sustained.

A request for comment from the U.S. Fifth Fleet, which is stationed in the Gulf and has deployed naval personnel alongside Britain to defend Red Sea shipping against an increase in Houthi attacks, was not immediately answered.

The Houthi official’s allegation of a missile and drone volley against an American ship may or may not have been related to British and American naval operations.

Targeting Red Sea commercial lanes, the Houthis, who hold sway over much of Yemen, are demonstrating their support for the Palestinian Islamist organization Hamas. According to Germany’s foreign ministry, there has been a “clear escalation” in recent attacks.

The attacks have severely disrupted the crucial route between Europe and Asia, which accounts for 15% of global maritime trade.

Though some oil giants, refiners, and trade houses have persisted in using it, many shipping firms have been compelled to reroute their boats, using the more complicated path across Africa.

The two fleets fired down 18 drones, two anti-ship cruise missiles, and one anti-ship ballistic missile on Tuesday, according to U.S. Central Command.

Shapps said there was “a generalized attack on all shipping” and speculated that the Royal Navy ship HMS Diamond, which withstood the strikes alongside US warships, may have been primarily targeted.

The Houthis have threatened to strike American warships if the militia group itself is attacked, and they have pledged to keep up their attacks until Israel ends the fighting in Gaza.

For security considerations, the German shipping company Hapag Lloyd stated on Tuesday that it would avoid the Suez Canal and the area surrounding the Cape of Good Hope. Meanwhile, rival Danish company Maersk (Maersk. CO) said it would stay away from the route “for the foreseeable future.”.

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