UAE-backed Tihama Resistance forces in Yemen began protesting this week over non-payment of salaries in May and June.
The demonstrations could deeply impact gains already made by the Saudi-led Arab coalition in the strategic Red Sea port of Hudaydah.
The UAE has not commented on the issue.
Saudi Arabia and the UAE launched an offensive on Hudaydah on 12 June in the largest battle of the war that the United Nations fears risks triggering a famine in Yemen where an estimated 8.4 million people are on the verge of starvation. It was paused last week for peace talks, but no deal has been struck leaving Yemenis pessimistic over a viable political process.
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Early this morning, the Houthis executed a missile at Saudi Arabia, the second such strike in 24 hours. Today a short-range missile was fired towards the West Coast targeting the Saudi-led coalition.
Yesterday's attack saw a Badr-1 ballistic missile being fired at Saudi's Jizan region. Saudi Arabia has not confirmed if there were any civilian casualties or the extent of damage caused by the strike.
According to Saudi Arabia, the Houthis have fired some 158 missiles into the Kingdom since the conflict began in March 2015.
The coalition continues to accuse the Houthis of using Hudaydah to smuggle weapons from Iran despite its warships monitoring the Bab El Mandeb Strait. There has been no evidence to suggest that the Houthis are receiving arms via the port according to UN experts on Yemen.