US President Donald Trump vowed Monday that strikes on Yemen’s Huthis will continue until they are no longer a threat to shipping, warning the rebels and their Iranian backers of “real pain” to come.

“The choice for the Huthis is clear: Stop shooting at US ships, and we will stop shooting at you. Otherwise, we have only just begun, and the real pain is yet to come, for both the Huthis and their sponsors in Iran,” Trump said on his Truth Social platform.

Shortly after Trump’s threat, Yemeni rebel media said two US strikes Monday hit the island of Kamaran, off the Hodeida coast.

Huthi-held parts of Yemen have faced near-daily attacks since the US launched a military offensive on March 15 to stop them from threatening vessels in key maritime routes.

The first day alone, US officials said they killed senior Huthi leaders, while the rebels’ health ministry said 53 people were killed.

Since then, rebels have announced the continued targeting of US military ships and Israel.

In his post Monday, Trump added that the Huthis had been “decimated” by “relentless” strikes since March 15, saying that US forces “hit them every day and night — Harder and harder.”

Trump’s threat comes as his administration battles a scandal over the accidental leaking of a secret text chat by senior security officials on the Yemen strikes.

It also comes amid a sharpening of Trump’s rhetoric towards Tehran, with the president threatening that “there will be bombing” if Iran does not reach a deal on its nuclear program.

The Huthis began targeting shipping after the start of the Gaza war, claiming solidarity with Palestinians.

Huthi attacks have prevented ships from passing through the Suez Canal, a vital route that normally carries about 12 per cent of world shipping traffic. Ongoing attacks are forcing many companies into a costly detour around the tip of southern Africa.