The United States carried out new airstrikes on Yemen, the Houthis' Al Masirah TV said, expanding the biggest U.S. military operation in the Middle East since President Donald Trump took office in January.

Yemen's Houthi rebels say there have been fresh US strikes against them, with the number of dead rising to 53, including five children. Targets in the Al Jaouf and Hudaydah areas were hit early on Monday, according to the rebel group, while the US Central Command said its forces had continued operations.