By Ali Oweida and Mohamed al-Samei

MAARIB, Yemen

UN envoy to Yemen Ismail Ould Cheikh Ahmed arrived in capital Sanaa on Thursday, a week after unveiling a plan for ending the country’s two-year-old conflict.

An official source at Sanaa’s international airport, who spoke to Anadolu Agency anonymously due to restrictions on speaking to media, said Ahmed had arrived from Djibouti.

The source did not elaborate further.

While in Sanaa, the UN envoy is expected to discuss his peace plan with representatives of both the Shia Houthi militia and allied forces loyal to former Yemeni president Ali Abdullah Saleh.

Ahmed’s arrival in Sanaa prompted demonstrations in Yemen’s Maarib and Taiz provinces by groups opposed to the peace plan.

The demonstrations were reportedly organized by groups that support the Saudi-backed government of President Abd Rabbuh Mansour Hadi.

Many protestors raised banners denouncing Ahmed’s peace plan.

"The UN peace plan paves the way for war," one read. Another asserted that the plan "legitimizes the Houthis’ 2014 coup".

"We demand the UN end the Houthi coup against Yemen’s legitimate authorities and stop the group from threatening maritime activity in the Red Sea and Bab el-Mandab," read a joint statement issued by demonstrators.

"We further call on the [Saudi-led] Arab coalition to take decisive military action if the Houthis reject peace," the statement added.

Unity govt

At a Monday briefing, Ahmed told members of the UN Security Council that his peace plan envisaged the appointment of a new Yemeni vice-president and the formation of a national unity government.

The plan also calls for the establishment of military and security "committees" tasked with overseeing the eventual surrender of weapons by the Houthis and their eventual withdrawal from the cities of Sanaa, Hodeida and Taiz.

Last Saturday, Hadi voiced his rejection of the peace plan, saying it "rewards the putschists [i.e., the Houthis] and sows the seeds of war".

Earlier this year, Hadi’s government and the Houthis engaged in two rounds of UN-sponsored peace talks in Kuwait, neither of which registered any breakthroughs.

Yemen has been wracked by chaos since late 2014, when the Houthis and their allies overran Sanaa and other parts of the country, forcing Hadi and his Saudi-backed government to temporarily flee to Riyadh.

The conflict escalated in March of last year when Saudi Arabia and its Sunni-Muslim allies launched a massive military campaign aimed at reversing Houthi gains and restoring Hadi’s embattled government.

Since the conflict erupted two years ago, thousands of people are believed to have been killed in the violence and some 3 million forced to flee their homes.