AMMAN — US President Donald Trump said Yemen’s Houthis were “misbehaving very badly” as the Iran-backed group stepped up missile and drone attacks on Saudi Arabia.

 

Trump did not outline any specific US response.

 

“Well, the Houthis are misbehaving very badly. No good,” Trump told reporters late on Monday as he departed the White House for Ohio, when asked what he planned to do about the group.

 

The remarks came after repeated Houthi attacks on Saudi Arabia, including strikes on King Khalid International Airport in Riyadh that, authorities there said, killed at least 13 people and wounded more than 300 over the weekend.

 

A Houthi official on Monday warned the US it would receive a "painful response" if it entered the war in Yemen.

 

The Houthis began targeting Saudi oil facilities, tankers and transport hubs, including a string of lethal strikes on Riyadh's airport.

 

Blasts resounded over the capital again on Monday night, with the Saudi coalition saying it had intercepted a Houthi missile and the group saying it had again targeted the airport, AFP reported.

 

Following an attack at the facility on Saturday that killed 13 people, US President Donald Trump said he was considering joining Saudi strikes against the group, after having reportedly rebuffed previous requests for help from the kingdom.

 

"If the US becomes involved in the aggression against Yemen, we will not deliberate over the decision to respond, rather, there will be a swift and painful response targeting the US and all its interests in the region," Houthi political bureau member Mohammed Al Bukhaiti told AFP in an interview.

 

He also warned "all employees and workers at Saudi oil facilities and airports to stay away from these sites, as they have become legitimate targets".

 

Saturday's strike on King Khalid International Airport was the deadliest attack on Saudi soil in more than a decade, and also left hundreds wounded.

 

Trump said the attack was "not acceptable" and that he would be speaking to the kingdom's Crown Prince Mohammed bin Salman, telling reporters the US was "going to look at" the possibility of joining Saudi strikes.

 

Saudi energy minister Prince Abdulaziz bin Salman told a conference in Riyadh on Monday that the recent events had "tested our infrastructure, our institutions, our people, and our resilience".

 

"The events of recent weeks are serious, our response must be equally serious."

 

CCTV footage of Saturday's attack released by Saudi authorities showed Muslim pilgrims in religious attire waiting in departure lounges before a sudden blast tore through the building and brought down flaming debris.

 

The atmosphere in Riyadh remained tense on Monday, as state broadcaster Al Ekhbariya said the military coalition was responding to drone and missile threats.