Dozens of armoured vehicles belonging to Islah Party militants were reported to have moved from Marib province to Shabwa yesterday according to sources.
It has also been reported that large Saudi weapons systems also belonging to Islah fighters have been heading towards the province which is contested between the forces of the UAE-backed Southern Transitional Council (STC) and the Saudi-backed Yemeni government.
This comes as Saudi Arabia boosted its troops and armoured vehicles in the same province over the weekend, raising the risk of clashes between the Gulf neighbours.
Reports also claim that the UAE has sent more troops to the port city of Aden today. At least 70 UAE combat vehicles were seen arriving on a vessel and deployed to a camp of STC loyalists, the Security Belt Forces.
STC forces have taken control of the de facto capital from the Yemeni government last month.
Pro-separatist social media accounts have also highlighted rallies taking place today in support of the UAE military presence in the south.
The STC has accused the Muslim Brotherhood aligned Islah Party of aiding the Houthis in the north and although Saudi Arabia has been seeking to contain Muslim Brotherhood influence in the wider region, it appears to have aligned with the Islah fighters further complicating the conflict.
Social media users have circulated a fatwa, religious edict, believed to have been issued by the Board of Ulema (religious leaders) in Yemen which commends Saudi Arabia for its support and beseeches its help in putting an end to UAE air strikes and refers to the STC as an insurgency.
The document argues that disunity in the south only benefits the Houthis and the "Iranian project" in Yemen; calling on Yemenis to "eliminate the insurgency" in the south and to restore the "kidnapped" capital, Sanaa, away from Houthi control.