Men inspect a damaged petrol station after it was hit by a previous alleged Saudi-led coalition airstrike on the outskirts the Yemeni capital Sanaa on May 21, 2018

A woman was among four people killed in an air strike that hit a petrol station in Yemen's rebel-held capital late Saturday, medical sources said.

Eleven people were wounded in the air strike on Sanaa, they said.

Witnesses said it took place just before sunset as people prepared to break the dawn-to-dusk Islamic fast of Ramadan.

It was not immediately clear who had carried out the strike.

Saudi Arabia, which leads a military coalition that has been fighting the Huthi rebels since 2015 to shore up the internationally recognised government, is active almost daily in Yemen.

Earlier Saturday, Riyadh reported that two soldiers from its national guard had been killed in fighting against the Huthis along the kingdom's southern border with Yemen.

The official SPA news agency did not provide details on when or how they died.

The report came as coalition spokesman Colonel Turki al-Maliki said Saudi air defences had intercepted and destroyed a Huthi drone that targeted the international airport of the southern city of Abha.

An examination of the debris showed the drone was manufactured by Iran and used by the Huthi rebels, Maliki said in a statement late Saturday cited by the SPA.

The Saudi-led coalition launched a military intervention in Yemen in 2015 after the Iran-allied Huthis expelled pro-government forces from Sanaa and went on to seize swathes of the country.

The conflict has left nearly 10,000 people dead, tens of thousands wounded, and millions on the brink of famine in what the United Nations has called the world's worst humanitarian crisis.

In addition, more than 2,200 others have died from cholera and millions are on the verge of famine in what the United Nations says is the world's gravest humanitarian crisis.

Mark Lowcock, the United Nation's humanitarian affairs chief, said Thursday that "some 8.4 million people are severely food insecure and at risk of starvation" in Yemen.

"If conditions do not improve, a further 10 million people will fall into this category by the end of the year," he warned.