Thousands rally against Houthi militia control in Yemen

Thousands of Yemenis took to the streets of Sanaa on Saturday in the largest demonstration against the Houthi since the Shiite militiamen overran the capital in September.

"Down, down with the Houthi rule," chanted the protesters who rallied following a call by the Rejection Movement - a group recently formed in provincial areas to challenge the powerful militia.

Dozens of Houthi supporters tried to stop the demonstration, triggering a brief scuffle, before they left as the numbers of protesters kept increasing, an AFP correspondent reported.

Demonstrators gathered in Change Square near the University of Sanaa before they headed for Republican Palace, in central Sanaa, according to organisers.

The palace is the residence of Prime Minister Khalid Bahah, who left it on Wednesday for an unknown destination after a two-day siege by the militia.

But the protesters changed their route and headed toward the residence of embattled President Abdrabbuh Mansour Hadi to express their "rejection of his resignation," according to the organising committee.

The demonstrators were also demanding that Hadi "impose the authority of the state" in face of the tightening grip of the Houthis on power, the organising committee said.

Hadi tendered his resignation on Thursday saying he could no longer stay in office as the country was in "total deadlock". 

Demonstrations also took off in the cities of Taez, Ibb and Hudaida, organisers said.

Power vacuum after president quits

Yemen is now facing a dangerous power vacuum after the president's resignation.

Bahah also tendered his resignation, saying he did want to be part of the collapse of the country.

A senior State Department official said staffing at the US embassy in Sanaa, already thin after most of the diplomatic personnel were ordered to leave in September, would be further reduced.

Parliament is set to hold an extraordinary meeting to discuss Hadi's resignation offer, which needs to be approved by lawmakers to take effect.

Hadi advisor Sultan al-Atwani told AFP that parliament would meet on Sunday "at the earliest" because it is in recess and lawmakers need time to return.

Witnesses and security forces said that Houthi militiamen had encircled the parliament building overnight, having already seized the presidential palace earlier this week.

Gunmen have also surrounded the houses of top officials including Defence Minister Mahmud al-Subaihi and head of intelligence Ali al-Ahmedi, a security official said.

Yemen has been riven by instability since an uprising forced strongman Ali Abdullah Saleh from power in 2012.

Saleh has been accused of backing the Houthi - who are from the same Zaidi sect of Shiite Islam as the ex-leader - as has Iran.

While the situation was generally calm in Sanaa, two small explosions targeted two houses belonging to Houthi members but there were no casualties.

After heavy fighting between government forces and the Houthi this week that killed at least 35 people, the UN Security Council had voiced support for Hadi's continued rule.

The situation escalated on Saturday when the militiamen seized top presidential aide Ahmed Awad bin Mubarak in an apparent bid to extract changes to a draft constitution opposed by the Houthi because it would divide Yemen into six federal regions.

The Houthi continue to hold Mubarak and maintain a tight grip on the capital despite a deal struck late on Wednesday to end what authorities called a coup attempt.

Southern anger at Houthi militants

Hadi is from Yemen's formerly independent south and in recent days southern officials have taken steps to back his rule, including closing the airport and seaports in the main city of Aden.

The security and military committee for four of south Yemen's provinces, including Aden, said late Thursday it would not take orders from Sanaa following Hadi's resignation.

The committee in charge of military and security affairs for Aden, Abyan, Lahej and Daleh, placed police and troops on alert across the four provinces.

It instructed them to take orders only from the provincial governors and the fourth military region command in Aden, whose officers are Hadi loyalists.

It condemned the "tragic events in Sanaa and the totally unacceptable demands made by the Houthi," the Shiite militiamen who have controlled much of the capital since September.

The formerly independent south has three other provinces further east - Shabwa, Hadramawt and Mahra.

UN Secretary General Ban Ki-moon called on all sides "to exercise maximum restraint and maintain peace and stability," his spokesman said.

His envoy to Yemen, Moroccan diplomat Jamal Benomar, had arrived in the country on Thursday for talks with the political rivals, but they were swiftly overtaken by events.

Oxfam has warned that 16 million people - more than half the population - were in need of aid in Yemen.

"A humanitarian crisis of extreme proportions is at risk of unfolding in the country if instability continues," the aid group said.