WASHINGTON - Saudi Arabia and its coalition partner in Yemen, the United Arab Emirates (UAE) transferred US-made weapons to al-Qaeda-linked groups and a Salafi militia whose commander who once "served with" the Yemeni branch of ISIL, a CNN investigation has found.

Corroborating an earlier report by Al Jazeera, the CNN investigation said that the weapons had also made their way into the hands of Houthi rebels who are battling against the coalition for control of the country.

Saudi Arabia and the UAE entered Yemen's war in 2015 leading a military coalition to try and restore the internationally recognised government of President Abd-Rabbu Mansour Hadi.

The two Gulf countries wanted to restore the Hadi government after a civil war broke out between Hadi's supporters and those loyal to the Houthis.

But according to CNN, the coalition was using US-manufactured weapons "as a form of currency to buy the loyalties of militias or tribes, bolster chosen armed actors, and influence the complex political landscape," local commanders and analysts said.

According to the Pentagon, the Gulf monarchies were breaking the terms of their arms deal with Washington.

A US defence official told CNN that there was an ongoing investigation into the issue.(FA)