Houthi rebels, who deposed Yemen's government by force, have come to a preliminary agreement for a new government, showing willingness to negotiate, a U.N. official said Friday.

It's a breakthrough, said envoy Jamal Benomar. But it's not a final deal.

Parties to the negotiations are hopeful it will prevent a civil war. It represents a shift of the Houthis' tone from just a month ago, when they stormed the capital Sanaa with guns blazing.

Armed takeover

After a years-long conflict with the government, the rebels attacked the residences of President Abdurabu Hadi and Prime Minister Khaled Bahah last month.

When the two refused to concede the Houthis' political demands, the rebels, who are Shiites in a majority Sunni nation, forced them to resign.

The offensive and takeover stunned governments in the West, who, along with other countries, pulled out diplomatic staff. Houthi fighters took U.S. Embassy vehicles and would not let departing Marines take their weapons with them.

But Western governments have other worries as well.

Fight against AQAP shaky

Yemen's former government was allied with the United States and other Western and Middle Eastern powers in the fight against al Qaeda in the Arabian Peninsula -- who are Sunni Islamist extremists.

There has been little sign so far of how willing to negotiate the Shia Zaidi Houthis, who are supported by Iran and who have been secessionists, might be.

The U.N. envoy is helping broker the preliminary agreement between Houthi leaders and the independent, relatively new Justice and Building Party.

The Houthis applied pressure to get results, threatening to escalate violence, if no deal were reached, said Justice and Building Party spokesman Baligh al-Mikhlafi. "This deal is not perfect, but it ensures that Yemen does not collapse," he said.

A rough agreement

The agreement outlines only rough points.

"There are still a number of issues on the dialogue table that must be agreed on dealing with the government and presidency as well guarantees for the implementation of the deal," Benomar said.

Yemen's legislative body, the National Congress, will get a second chamber -- a brand new parliament.

The Houthis, who live in Yemen's north, will get 50% of the seats and concede 50% to the country's south. Half of seats will go to the country's women and youths, Benomar said.

The current House of Representatives will remain as it is for now.

The U.N. had called for Houthi fighters to withdraw from government institutions it had captured. Whatever the military concessions, the agreement allows Houthi gunmen to remain in Sanaa.

CNN