Heavy fighting between government loyalists and rebels for control of Yemen's third city Taez has killed more than 80 people in the past 24 hours.

Pro-government and rebel forces have for months fought over Taez, seen as crucial gateway to the rebel-held capital Sanaa.

But clashes in the city have intensified in recent days after pro-government forces made sweeping territorial gains against the Iran-backed rebels in southern Yemen.

Sources in the city told AFP that the bodies of 50 rebels and allied fighters were recovered from Taez on Monday and that 31 pro-government fighters had been killed.

Backed by air strikes from a Saudi-led coalition, the loyalists have been pushing hard to take Taez, seizing several strategic locations on Sunday.

Coalition strikes continued to hit rebel positions in the city on Monday, witnesses said, as well as in other Yemeni provinces.

The battle for Taez is expected to be difficult for the loyalists, analysts say, with recent victories by pro-government forces in Yemen's south likely the result of rebels pulling their forces back to the city.

Yemen has been wracked by conflict since March, when the Saudi-led coalition launched air strikes against the rebels as they advanced on the main southern city of Aden, after seizing the capital in September.

Forces loyal to President Abedrabbo Mansour Hadi, in exile in Saudi Arabia, have in recent weeks retaken Aden and several southern provinces.