Southern Transitional Council conflict
The Southern Transitional Council conflict was a sub-conflict of the Yemeni Civil War, between the separatist Southern Transitional Council (STC) and other factions, mainly the internationally-backed government in Yemen. The STC was supported by the United Arab Emirates, despite the UAE being a member of the Saudi Arabian-led coalition working to support the Yemeni government.
Source: Wikipedia — Southern Transitional Council conflict (CC BY-SA 4.0)