A UN envoy returns to Yemen on Thursday in a fresh bid to persuade Ali Abdullah Saleh to hand over power under a Gulf-brokered peace plan, following reports the president is inching towards accepting the proposal.

Officials said Jamal Benomar would meet Vice President Abd-Rabbu Mansour Hadi, who has been mandated by Saleh to negotiate details of the handover deal with an alliance of opposition parties and sign it.

Benomar will also meet opposition leaders as part of the effort to implement the proposal brokered by the six-member Gulf Cooperation Council in April to end protests by Yemeni demanding that Saleh step down after 33 years in office.

We are waiting for the leaders of the opposition and Benomar to arrive in Sanaa tomorrow (Thursday) to resume discussions on details of the Gulf initiative so it can be signed, the head of the information department at the ruling General People's Congress party, Tareq al-Shami, told Reuters.

Yemen has been rocked by months of protests that have put one of the poorest countries in the Arab world on the brink of civil war, a situation that could threaten the stability of neighbouring Saudi Arabia, the world's largest oil exporter.

Opposition sources said that under the Gulf plan, Saleh would issue a decree handing over all powers to Hadi. The vice president would then sign the Gulf initiative and name an opposition politician to form a new national unity government that would start preparing for early elections.

If Benomar's mission is successful, the accord is expected to be signed in a ceremony in Saudi Arabia by mid-November, Yemeni officials said.

Benomar's trip comes after France said the European Union planned to discuss freezing Saleh's assets. The U.N. Security Council has unanimously condemned Yemen's crackdown on protesters and urged Saleh to sign the Gulf-brokered peace deal.

Saleh has backed away three times in the past from signing the Gulf plan, adding conditions including remaining president until a new head of state was elected, according to officials.

But Saleh has recently said he has dropped such conditions and intends to leave office once the peace plan is signed.

An opposition spokeswoman was sceptical.

We cannot say there is real progress regarding any transfer of power until the Gulf initiative has been signed, Houriya Mashhour, of the opposition's National Council of the Revolution, told Reuters.

(Reporting by Mohammed al-Ghobari; Writing by Sami Aboudi; Editing by Andrew Roche)