At least 68 fighters have been killed in two days of fierce battles between Yemeni forces and Huthi rebels near the strategic Bab al-Mandab strait, military officials said Sunday.

Government forces launched on Saturday an assault to recapture the coastal Dhubab district, just 30 kilometres north of Bab al-Mandab which links the Red Sea and the Indian Ocean.

Since then at least 55 Huthis have been killed in fighting and 72 others wounded, military and medical sources said.

Clashes since Saturday have also killed 13 loyalists forces, including an army general, Brigadier-General Abdul Aziz al-Majidi, a loyalist commander, told AFP.

Landmines planted by the rebels have slowed down the advance of government forces, military officials said.

The government and its allies recaptured Bab al-Mandab strait in October 2015, pushing the Iran-backed rebels further north.

But the rebels still control nearly all of Yemen's Red Sea coast to the north, posing what the coalition says is a threat to international shipping.

In September and October, two US warships and a United Arab Emirates vessel contracted to the coalition were targeted by missile fire from rebel-held territory.

Pro-government troops seized Dhubab in early October 2015, but the rebels managed to recapture the area in February.

The Yemeni conflict has killed more than 7,000 people since the coalition's military intervention began in March 2015, according to the United Nations.