UAE-aligned separatists in southern Yemen have warned of an “imminent war” against Saudi-supported mercenaries, fighting on behalf of the UN-recognised Yemeni government, based in Riyadh.

The UAE and Saudi are joint-leaders of the US-backed coalition which has been waging a five-year war on Yemen, in a bid to topple the Houthi-led government ruling from the capital Sanaa in order to reinstate President Abd Rabbuh Mansour Hadi.

A statement issued by the Southern Transitional Council (STC) said it had informed foreign ambassadors and UN envoy Martin Griffiths that “the outbreak of war is imminent”.

The so-called “Riyadh Agreement” signed in the Saudi capital last year between Hadi and the STC was hoped to usher in a power-sharing settlement to shift focus away from in-fighting towards a unified front against the Yemeni armed forces allied with the Houthis. However this has failed to materialise, with the STC accusing the Hadi government of violating the agreement to regain control over the south, including the port city of Aden, currently under STC control. The city had served as the de facto capital for the government until it was seized in August last year.

READ: Saudi-backed Yemen government says ceasefire agreement ‘unenforceable’

Clashes between the STC-affiliated Security Belt militia and the Saudi-sponsored Islah forces continue to occur in the Shabwa and Abyan provinces. On Saturday, it was reported that the separatist militias carried out three surprise ambush attacks against an Islah convoy who were allegedly on their way as reinforcements to a military camp in the coastal city of Shaqra.

On Friday, the Islah Party announced its intention to storm Aden following the latest failure in mediation efforts in Shabwa and Abyan.

Griffiths said on Friday that he expects a ceasefire between the warring parties to be reached “in the immediate future”.

#Yemen #Marib update; significant progress can be seen as the Yemeni Army and Ansarallah have opened another front against Al-Islah just south of the Kofal base: pic.twitter.com/Q5CM7Mwe7u — Majster 🇵🇱 (@Majster06475099) April 19, 2020

“We are redoubling our efforts to bridge the outstanding differences between the parties,” he said, adding that the city of Marib east of Sanaa “remains the centre of gravity of this war”. Marib is the remaining Islah-stronghold in the face of continued advances being made by the Houthi’s army forces.

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