WASHINGTON/SANAA/CAIRO – US President Donald Trump said Tuesday that the Houthis, a Yemen-based armed group, have posed no recent challenge in the Red Sea and that US forces would respond if necessary.

"So far, it hasn't happened," Trump told reporters while meeting Lebanese President Joseph Aoun at the White House. "If something like that happens, we take care of it," he added.

"They've had no problem with us for a long period of time, including during this (US-Iran) conflict," he said, referring to the Houthis. "I think that if there is something like that, we'll just have to take care of business."

The Houthi group has warned international shipping companies that vessels trading with Saudi ports could face military action, in what appears to be an escalation following the group's maritime ban announcement against Saudi Arabia.

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An advisory email issued late Monday by the group's Sanaa-based Humanitarian Operations Coordination Center said the warnings cover not only Saudi-flagged vessels but also ships loading or unloading cargo at Saudi ports.

The advisory came hours after the Houthis announced a maritime ban on Saudi shipping.

Chairman of Yemen's Presidential Leadership Council Rashad al-Alimi on Tuesday warned that the Houthi group's threats could have broader implications for security in the Red Sea.

A blockade of the Red Sea, a vital corridor for international trade and energy shipments, could heighten tensions in the Middle East and disrupt regional oil flows.

The Houthis have previously used missiles, drones, and naval weapons against vessels they accused of being linked to Israel and the United States during the Gaza war, forcing shipping companies to divert vessels away from the Red Sea.

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On Tuesday, Arab League Secretary-General Nabil Fahmy condemned recent "threats" by the Houthi group against Saudi Arabia, describing them as a dangerous and unacceptable escalation that could further inflame regional tensions.

In a statement, Fahmy voiced the Arab League's full solidarity and support for Saudi Arabia in confronting any actions that could undermine its security, stability or sovereignty.

'6 vessels turned back'

The group said on Tuesday that six commercial vessels had "turned back over the past 24 hours" after receiving warnings issued under its newly announced maritime restrictions targeting Saudi-linked shipping, the Houthi-run Saba news agency reported, citing military sources within the group.

The report did not identify the ships or specify their locations, destinations or nationalities, and the claim could not be independently verified.