At least 15 Yemeni rebels and eight soldiers were killed Monday as government forces attacked insurgent positions in two areas in the southwest of the country, military officials said.

Loyalists attacked Shia Houthi rebels and their allies, renegade troops loyal to ex-president Ali Abdullah Saleh, at Heess, on the road linking the city of Taez with Hodeida port, on the Red Sea coast, officials said.

The attack aimed to block the road leading to the rebel-held port, the officials said.

The second attack targeted rebels in Al-Hameli area, north of the port of Mokha, which was recaptured by government forces in February as part of a major ongoing offensive to drive rebels from the lengthy Red Sea coastline.

Several soldiers were wounded in the clashes, officials said.

Warplanes from the Saudi-led Arab coalition backed government forces in the attacks, officials said.

The coalition mounted a military operation against the rebels in March 2015 as insurgents closed in on President Abedrabbo Mansour Hadi in his southern refuge in Aden forcing him to flee to Riyadh.

Government forces have since recaptured five southern provinces, including the city of Aden, which has become a temporary base for Hadi's internationally recognised government.

Meanwhile, a suicide bomber rammed on Monday an explosives-laden vehicle into the gate of a military base in the district of Ain Bamaabad, in the southern Shabwa province, a security official said.

The attack killed at least three soldiers, the official added.

The World Health Organization estimates that more than 8,000 people have been killed in Yemen's conflict, most of them civilians, since March 2015.

The country has also been hit by a deadly cholera outbreak and is on the edge of famine.