A group of separatists in southern Yemen, backed by the United Arab Emirates (UAE), has declared a state of emergency in the port city of Aden and vowed to overthrow the country's internationally recognised government within the next week.

Aidarous al-Zubaidi, the leader of the Southern Transitional Council (STC), said Yemen's parliament would be barred from convening in Aden or anywhere else in southern Yemen unless President Abd-Rabbu Mansour Hadi replaced Prime Minister Ahmed bin Daghr and his entire cabinet.

Speaking at a meeting on Sunday, al-Zubaidi accused Hadi’s government of "rampant corruption" and of "waging a misinformation campaign against the southern leaders using state funds".

"The Southern Resistance Forces (SRF) declare a state of emergency in Aden and announce that it has begun the process of overthrowing the legitimate government and replacing it with a cabinet of technocrats," a statement issued by the STC said.

The SRF, an armed group that has clashed with forces loyal to Hadi for control of strategic areas including Aden airport, will "become the core of a new force that will rebuild South Yemen's security and military institutions," the statement added.

Several commanders from security forces set up by the UAE attended the meeting and declared their support for the announcement.

The statement, however, did not give details on how it intended to topple Hadi's government, only that he had a week to comply.

Different agendas?

The announcement underscores rising tensions between Hadi's government, which is supported by Saudi Arabia, and the southern separatists, who are backed by the UAE.

The UAE entered Yemen's war in March 2015 as part of a Saudi-led coalition after Houthi rebels, traditionally based in the northwest of the country, overran much of the country, including the capital Sanaa, in 2014.

Nearly three years on, Saudi Arabia has said it "wants out" of the war, but the UAE has become more involved in the conflict, indicating a divide in the two countries' agendas.

The UAE has been financing and training armed groups in the south of the country who answer to al-Zubaidi, a 50-year-old militia leader who emerged from relative obscurity in late 2015 after helping purge the Houthis from Aden.

Al-Zubaidi was initially rewarded and made governor of Aden by Hadi, but soon fell out of favour after reports emerged he was receiving patronage from the UAE to campaign for secession.

The Middle East Eye news website, quoting sources, reported that Hadi was incensed with the UAE, accusing Abu Dhabi Crown Prince Mohammed bin Zayed of acting as an occupying force, as opposed to a liberation force.

Hadi's weakening has gone hand-in-hand with the UAE's growing power in southern Yemen.

The Gulf nation has financed a network of militias that only answer to it, set up prisons, and created a security establishment parallel to Hadi's government, according to Human Rights Watch.

The Arab coalition has so far failed to achieve its stated aims as Houthi rebels continue to hold the capital Sanaa and much of the north.

The war has taken a huge toll on the country with more than 60,000 people killed and wounded by fighting, and millions of Yemenis at risk of famine amid a massive cholera outbreak.