This weekend's deadly attacks on Riyadh's main airport have demonstrated the ability of Yemen's Houthis to strike at the heart of Saudi power, raising the risk of a dangerous escalation that could draw in the US.Saturday's strike killed 12 people and wounded 309, while an attack on Sunday killed one person and injured 11.

The Houthis swiftly claimed the attacks, saying they were a response to "Saudi aggression," including a strike on the airport in the Yemeni capital of Sanaa.Saudi fighter jets are already backing a counteroffensive by Yemeni government forces after the Houthis seized territory near Bab el-Mandeb, a critical chokepoint for global shipping at the southern entrance to the Red Sea.The Houthis had largely stayed on the sidelines after the US-Israeli war against Iran began in February.

But the latest offensive illustrates how the group - a member of Iran's so-called axis of resistance - has developed into its own autonomous fighting force, with its own sophisticated weapons supply chain and an ability to operate and escalate as they see fit, at times in coordination with the Islamic Republic.ALSO READ | 'Unacceptable': India Condemns 'Dastardly' Riyadh Airport Missile Strike That Killed 12Despite the airport strikes and fresh tanker attacks around the Strait of Hormuz, oil dropped on Monday.

Traders instead weighed President Donald Trump's claim of an energy ceasefire between Russia and Ukraine, with Brent crude slipping below $104 a barrel after a two-day gain.The attacks put de facto ruler Crown Prince Mohammed bin Salman under mounting pressure to escalate a war the country has spent years trying to escape, against an opponent that's arguably more capable than it's ever been.

They also present difficult choices for the US and the kingdom's new defense partners, Turkey and Pakistan, over how far to go in helping Saudi Arabia respond."By escalating their attacks, they are trying to pressure Saudi Arabia into stepping back and halting its air campaign," said Ahmed Nagi, the International Crisis Group's senior analyst for Yemen.

"Riyadh sees these strikes as a serious escalation, particularly given their unprecedented nature, and is likely to respond with greater military pressure."With an American among those killed on Saturday, Trump also faces growing pressure to act.

Asked on Saturday whether the US would join strikes against the Houthis, he said: "We may.

We're going to look at it.""Riyadh will want direct US strikes against the Houthis, air defense capabilities, increased intelligence sharing, and political cover for an intensified campaign in Yemen," said William Usher, a former senior Middle East analyst at the Central Intelligence Agency.The Saudi-led coalition blamed the Houthis for Saturday's attack, calling it "a full-fledged war crime."Saudi Arabia led a coalition that intervened in Yemen in 2015 to restore the internationally recognized government, only to spend years bombing the Houthis without dislodging them.

A UN-brokered truce in 2022 sharply reduced the fighting and offered Riyadh a way to wind down its involvement while the militant group's capabilities and reach grew.Saudi Arabia's Foreign Minister Prince Faisal bin Farhan and his Iranian counterpart Abbas Araghchi discussed the latest escalation in the region in a phone call, according to a report Sunday by the state-run Saudi Press Agency.ALSO READ | Houthis Escalate Attacks, Plane Hit At Riyadh Airport; Videos Surface OnlineSaudi Arabia has spent billions of dollars building one of the region's most sophisticated militaries, equipped with American F-15 fighter jets and Patriot missile defenses whose interceptors cost as much as $5 million apiece.

Yet repeated strikes have shuttered the international airport serving its capital, grounding hundreds of flights and forcing schools to move online.The attacks may be a sign of the pressure the Houthis are facing in Yemen.

After the group seized the Red Sea port of Mokha and territory near Bab el-Mandeb last month, Yemeni government forces launched a....