WASHINGTON threatened to join the Saudi-led war on Yemen on Tuesday night, using Monday’s alleged missile attack on a US warship as a pretext.

The US Defence Department mooted possible air raids on troops and Houthi militia and their self-declared Supreme Political Council government.

The threat came the day after two missiles splashed harmlessly into the Red Sea near where the destroyer USS Mason and amphibious troop ship USS Ponce were cruising.

Yemen’s Sabah news agency quoted an anonymous Yemeni Republican Guard source as denying that the armed forces had fired on the US vessels.

Asked if the Obama administration was planning a retaliatory attack, Pentagon spokesman Captain Jeff Davis said: “Those things are things that we’re looking at. We’re going to find out who did this and we’ll take action accordingly.”

Capt Davis warned: “We will make sure that anybody who interferes with freedom of navigation or anybody who puts US navy ships at risk understands that they do so at their own peril.”

It followed Saturday’s air strike by the Saudi-led invasion coalition on the funeral of Interior Minister Galal al-Rawishan, which killed 155 mourners and wounded more than 500 in the capital Sanaa.

The latest coalition atrocity may have been in revenge for the Republican Guard’s sinking of an Emirati warship in the Red Sea on October 1.

US State Department spokesman John Kirby sought to excuse the funeral bombing on Tuesday, asserting that the coalition was not “deliberately targeting civilians.”

He argued that Yemen’s government had invited the Saudis to bomb its own country, referring to the Riyadh-based government in exile of ousted president Abed Rabbo Mansour Hadi, which the Saudis want to restore to power.

Mr Kirby also repeated claims that Iran was supplying arms to the Houthi-backed government.

Documents obtained by news agency Reuters this week through a freedom of information request showed that the White House had approved $1.3 billion (£1.1 million) in arms sales to Riyadh last year, despite concerns over possible Saudi war crimes.

Pentagon officials voiced doubt that coalition air forces could hit military targets without also killing civilians and destroying “critical infrastructure.”