A Saudi-led alliance has deployed 10,000 troops to Yemen, Qatari news channel Al Jazeera said on Tuesday, in an apparent sign of determination to rout Iran-allied Houthi forces after they killed at least 60 Gulf Arab soldiers on Friday.

Yemen's neighbours ramped up air strikes on the capital Sanaa on Tuesday and hope to launch a decisive assault soon on the city which the militia seized last year.

"The number of coalition soldiers who have already entered Yemen has risen to 10,000," Jazeera correspondent Abdul Mahsi Al-Sheikh reported from southern Saudi Arabia.

"A second contingent of Qatari soldiers will arrive today to Yemen after entering the Al-Wadee border crossing (with Saudi Arabia) ... as coalition forces have added to their military equipment with 30 Apache helicopters, armoured vehicles and rocket launchers," he added.

Qatari and coalition officials did not immediately respond to requests for comment.

Yemen's government fled to Riyadh in late March as Houthi forces, who say they are fighting a revolution against them, closed in on their last redoubt in Aden, triggering the foreign intervention and fighting which has killed over 4,500 people.

The Arab alliance states see their campaign as a fight against creeping Iranian influence in their backyard, but the Houthis deny being beholden to Tehran and say the exiled government in Riyadh and the coalition are American puppets.

Loyalist Yemeni forces and Gulf soldiers took back Aden and most of Yemen's south in July, but battle lines have barely moved since as the allied forces face stiff resistance in the Houthis' northern redoubts.

Houthi militiamen and their allies in Yemen's army fired a Soviet-era ballistic missile at an army base in the central province of Mareb on Friday, killing dozens of Emirati, Saudi and Bahraini troops.

The attack was the deadliest yet for Gulf soldiers in the war, and may herald a turning point in the conflict as countries appear to be committing to a ground war they had so far avoided.

Saudi-owned newspaper Al-Sharq Al-Awsat quoted coalition sources saying that some Egyptian and 6,000 Sudanese troops would soon join the fight inside Yemen. Their governments did not immediately comment.

But a source close to the Qatari military confirmed that the Gulf emirate was sending "mechanised infantry and armoured vehicles" and that Sudan had committed to send 6,000 troops.

"The operation in Sanaa ... will use extensive bombing, air power, to support the ground offensive," the source added. - Reuters