Saudi Arabia has joined Western states in evacuating staff from Yemen after a power grab by Houthi militia there, a move reflecting the hostility of majority Sunni Muslim neighbours towards the Iranian-backed Houthis.

Riyadh has suspended all work at its embassy in Yemen and evacuated its staff "due to the deterioration of the security and political situation", state news agency SPA reported on Friday, citing an official at the foreign ministry.

Germany and Italy also said on Friday they had closed their embassies in Yemen, following similar steps by Britain, France and the United States as the Houthis consolidated control after seizing the capital Sanaa in September.

A German Foreign Ministry spokeswoman said Berlin had shut down its mission on Thursday and staff left on Friday.

"In the past weeks the Houthis have seized power - this is unacceptably dangerous for us and could have consequences for the region," she said. "The situation is very concerning for us in Europe."

Italy also announced on Friday it had closed its embassy, citing a breakdown in security. It was withdrawing its ambassador and staff, the Foreign Ministry in Rome said.

Al Qaeda and other Sunni Muslim militants have stepped up attacks against Houthi fighters and U.N. Secretary-General Ban Ki-moon said on Thursday Yemen was "collapsing before our eyes" and slipping closer to outright civil war.

The Houthis have sidelined the central government in Yemen, which borders top oil exporter and regional heavyweight Saudi Arabia.

UN-backed negotiations on a political settlement continued in Sanaa on Friday. Thousands of Yemenis gathered after prayers in the mainly Sunni cities of Taaz, Ibb, Al-Bayda and Al-Hodeidah to denounce the Houthi takeover, witnesses said.

Riyadh along with other members of the Gulf Cooperation Council have accused the Houthi rebels of staging a coup in Yemen after they announced they were dissolving parliament and forming a new government last week.

Yemen has been in political limbo since the president and prime minister resigned last month after the Houthis seized the presidential palace.

Al Qaeda-linked fighters seized a large army base in a dawn attack in the southern province of Shabwa on Thursday, after several hours of heavy clashes.

In response, tribal fighters took over two other army barracks in Shabwa on Friday to prevent al Qaeda seizing more weapons and avoid a Houthi attack on the south, tribal sources told Reuters. - Reuters