Facing growing international and domestic pressure, Saudi Crown Prince Mohammed bin Salman's military campaign in Yemen has further pushed Riyadh to plead for Washington's assistance, according to a report.

Despite waging a prolonged four-year war on Yemen, the Saudi-led coalition has failed to achieve its announced objective of installing an allied government and defeating the Houthi Ansarullah movement in the country, The New York Times cited various analysts as saying.
The frustrated Saudis have, however, turned to additional US support in hopes of achieving a breakthrough, according to unnamed diplomats informed on the matter.
The US already provides the Saudis with weapons and logistical support. Riyadh is seeking additional intelligence assistance and possibly the deployment of American special forces teams and advisers in Yemen, according to diplomats.
Despite being emboldened by the US President Donald Trump's hawkish administration, Riyadh is, however, disgruntled with Washington's hesitation to provide the additional assistance.   
“Why haven’t the Americans carried out a single operation to help?” asked Mustafa Alani, a scholar at the Saudi-backed Gulf Research Center who is close to the royal court.
Washington's reluctance comes as the US congress has pushed to limit US assistance in the Saudi military campaign following the gruesome killing of Saudi journalist Jamal Khashoggi in a diplomatic mission in Turkey in October last year.
On Thursday, the US House of Representatives voted to pass resolutions that block certain arms sales to Saudi Arabia and the UAE.
US President Donald Trump has, nonetheless, strongly defended arm sales to the oil-rich kingdom. The president has vowed to veto any resolution banning the sales.