Yemen's dominant Houthi group said on Tuesday that President Abd-Rabbu Mansour Hadi had lost his legitimacy as head of state and he was being sought as a fugitive from justice.
Houthi militiamen seized the capital Sanaa in September and laid siege to Hadi's residence last month, prompting his resignation and leading to a political vacuum.
But Hadi escaped to Aden in southern Yemen last week after a month under house arrest and on Tuesday he officially recanted his resignation.
He now holds court guarded by thousands of tribesmen and army loyalists from the mainly Sunni Muslim south.
"The higher revolutionary committee is following the suspicious moves by Hadi, who lost his legitimacy to act as president of the Republic of Yemen, and whose reckless acts harmed the Yemeni people," the Houthi group said in a statement, its first official reaction since Hadi fled.
The power struggle between the Muslim Shi'ite Houthis in Sanaa and Hadi in Aden casts more doubt on United Nations-sponsored talks to resolve Yemen's crisis peacefully, and exacerbates sectarian and regional splits which may plunge the country into civil war.
Both sides have been racing to consolidate their claim to power. The Houthis say their push was a revolution which swept aside a corrupt government and President Hadi that he is the elected and internationally recognised leader.
"We are seeing a Libya-zation in Yemen. It's polarized between two competing governments. Thankfully unlike Libya, the competition hasn't descended into fighting – yet," said Farea al-Muslimi, a researcher with the Carnegie Middle East Centre.
INTERIM CAPITAL
Sources close to the president told Reuters he is considering declaring Aden as Yemen's interim capital until Sanaa is taken back from the Houthis. Loyalist army units and tribesmen from Hadi's neighbouring province of Abyan now run the city and much of the south.
The Houthis, who hail from the Zaydi sect of Shi'ite Islam that ruled Yemen's north for a 1,000 years before it became a republic in 1962, appear determined to quash Hadi's momentum.
They hope to swiftly patch together a caretaker government to replace the one that resigned along with Hadi and prime minister Khaled Bahah.
"Sixteen ministers from Bahah's government have agreed. Those who are refusing we will send to the general prosecutor on charges of treason against the nation," the group's al-Masirah television said.
The new tensions are making a negotiated solution less likely and increase the risk of a potential clash, which the Houthis' opponents hope will lead to their undoing.
"I am not optimistic of the success of the dialogue because the main party to it, President Hadi, is not represented there," Ahmed Kelz, a negotiator and a leader in an opposition party.
"I expect that just as the Houthis expanded into the north, west and centre of Yemen, they will be driven to push south and will drown there," he added.
