The US military campaign against Yemen’s Houthi rebels is only just beginning, Defence Secretary Pete Hegseth said on Monday.
The US last month started a campaign of strikes against the rebel group that controls much of Yemen and has wreaked havoc on international trade by attacking ships crossing the Red Sea.
“Whether it's underground facilities, weapons manufacturing, bunkers, troops in the open, air defence assets, we are not going to relent and it's only to get more unrelenting until the Houthis declare they will stop shooting at our ships,” Mr Hegseth told reporters in the Oval Office during a meeting between President Donald Trump and Israeli Prime Minister Benjamin Netanyahu.
“It's been a bad three weeks for the Houthis and it's about to get worse."
Mr Hegseth said the US campaign against the Houthis had been “devastating”, and officials have said the bombing campaign has successfully hit the Houthi military leadership.
The strikes have been been the focus of a scandal after it was revealed that top US officials including Mr Hegseth were discussing them in real time on the encrypted messaging app Signal, without being aware that a journalist had been accidentally added to the chat group.
At the weekend, the US campaign continued with strikes near the capital Sanaa. At least six people were killed, according to the Houthis.
"We've really hit them hard and they know it, and they don't know what to do," Mr Trump said. "And it's every night, night after night, and we've gotten many of the leaders and their experts."
Mr Hegseth said Washington has relayed to Iran, the Houthis' principal backer, that it should stop funding and supplying the group.
“We've been very clear to the Iranians as well,” he said. ”They should not continue to provide support to the Houthis. And that message has been made very clear."
The Houthis have said their attacks on the Red Sea will stop when Israel’s military campaign in the Gaza Strip ends.