ADEN, Yemen/MOSCOW - Yemen's Presidential Leadership Council (PLC) Chairman Rashad Al-Alimi called on the Saudi-led coalition on Friday to take "necessary military measures" to protect civilians in the southeastern province of Hadramout, as tensions with the Southern Transitional Council (STC) escalate, state media reported.

Al-Alimi made the remarks following a briefing on what Yemeni officials described as hostile operations and violations by the STC that threaten the stability of the oil-rich province, the state-run Saba news agency reported, citing a Yemeni government source.

The recent escalation, the source said, violates the transitional process and undermines Saudi-Emirati mediation efforts to de-escalate tensions and restore security.

Meanwhile, a military official within Yemen's internationally recognized government told Xinhua, on condition of anonymity, that the PLC request could trigger a new wave of Saudi airstrikes against STC forces in the coming hours.

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Local Yemeni forces, backed by heavy military equipment, have been deployed along a long stretch of the border with Saudi Arabia, the official said, adding that Riyadh could "intervene militarily" if the STC insists on maintaining its presence in Hadramout.

On Friday, the STC said Saudi warplanes carried out airstrikes on its military sites in Hadramout. Residents reported loud explosions across the province, and social media videos showed smoke rising from the targeted locations. The Saudi side has not officially claimed the attacks.

Tensions in Yemen escalated on Dec 3, when STC forces took control of Hadramout following clashes with pro-government units. The STC also criticized the PLC for failing to launch what it described as a serious campaign against the Houthi group.

Yemen has been mired in conflict since 2014, when Houthi forces captured Sanaa and large swathes of the north, prompting a Saudi-led coalition to intervene in 2015.

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The STC later expanded its presence into the eastern province of Al-Mahrah without reported resistance and has since recruited local forces in both provinces, despite repeated calls by the Yemeni government and Saudi Arabia for de-escalation.

Formed in 2017, the STC seeks self-determination and eventual independence for southern Yemen. Despite joining the Saudi-led coalition and integrating into the PLC in 2022, the group continues to push for southern sovereignty, leading to recurring disputes over power-sharing and control of resources.

The STC has accused previous Yemeni governments of politically and economically marginalizing the south, a claim Yemeni authorities reject, continuously stressing the importance of territorial unity.

Russia urges restraint

Also on Friday, Russian Foreign Ministry spokesperson Maria Zakharova said Moscow is concerned about the escalation of the military and political situation in Yemen and calls on all parties involved to exercise restraint.

She said that Russia calls on all parties involved to seek mutually acceptable compromise solutions to the existing problems and contradictions through constructive intra-Yemeni dialogue.

Russia welcomes the joint efforts by Saudi Arabia and the United Arab Emirates aimed at de-escalating tensions as soon as possible and stabilizing the situation in southern Yemen, Zakharova said.

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"We reaffirm our readiness to continue constructive engagement in pursuit of these goals with Yemen's official authorities and all influential political forces of this friendly country, as well as with Russia's partners in the region," she added.

Saudi warplanes on Friday carried out airstrikes on military sites affiliated with the Southern Transitional Council in Yemen's southeastern oil-rich province of Hadramout. Residents said that loud explosions were heard in parts of the province, while videos circulated on social media showed plumes of smoke rising from targeted areas following the air raids.