The Yemeni internationally-recognized government rejected anew on Tuesday the support provided by the United Arab Emirates to the Southern Transitional Council (STC) forces, calling for immediate halt.
"We refuse the continuation of Emirati financial and military support provided for the STC's unofficial, outlaw forces," said the official foreign undersecretary, reiterating "our call for stooping it immediately and completely."
"The unjustified escalation in Abyan governorate by the UAE-backed STC forces is refused and unaccepted," Mohamed al-Hadhrami added in a statement carried by his ministry website.
Escalation will "undermine and thwart mediation efforts" led by Saudi Arabia, he warned.
Earlier on Tuesday, local sources said violent clashes had erupted between the STC's Security Belt forces and Yemeni official special forces in the southern governorate of Abyan.
The SB forces have been besieging the security special forces camp in Zinjobar, Abyan provincial capital, calling for official troop withdrawal and camp handover, the sources added.
Escalation is "based on the special forces' support for the legitimate government and rejection of the STC coup in Aden," according to sources.
The official minister of information called "brethren to intervene rapidly and pressure the STC into stopping escalation and pulling back all its personnel."
By sieging the special forces camp, the SB is "challenging Saudi Arabia and rejecting its calls for de-escalation and dialogue," Moammar al-Eryani added on Twitter.
On August 10, the Emirati-backed separatist STC's forces seized full control over the Yemeni southern port city of Aden, seat of the official government, following violent clashes with official army that left 40 people killed and 260 others injured, according to UN release seizure of Aden.
The Yemeni legitimate government dismissed the STC seizure as another coup in Aden, following the Houthi coup in Sana'a, holding the UAE and STC responsible for ramifications.
Saudi Arabia, along with UAE, has been leading a military coalition in Yemen since 26 March 2015, in support of forces loyal to President Abd Rabbu Mansour Hadi to retake northern areas controlled by Houthi (Ansarullah) group.
Southern separatists have exploited Yemen's war to enhance their presence, backed by the UAE that helped establishment of STC in May 2017 to consist of Yemeni southern bodies calling for separation, but also trained and armed local forces under STC command.
The STC claims to be representative for Yemeni southerners and seeks to impose control over all the south, but it is not fully supported by people there.