Photo: Hannah McNeish/IRIN

Abandoned buildings in Abyei: One of the areas disputed by the two countries.

London — The Presidents of Ivory Coast and Equatorial Guinea have expressed willingness to back an African Union proposal to resolve the dispute between Sudan and South Sudan over the Abyei border region.

The African Union High-Level Implementation Panel (AUHIP) has proposed that a referendum to decide the future of Abyei be held in the oil-producing area in October, in line with the 2005 agreement that ended decades of Sudanese civil war.

Sudan has rejected the panel's position as it excludes members of the Misseriya - a Arab nomadic group who traditionally enter the region for part of the year with their cattle. The plebiscite was initially scheduled for January 2011 but was delayed as the two sides could not agree on who was allowed to take part.

Should the Misseriya be excluded, it is expected that the southern-aligned Dinka Ngok would decide to join South Sudan, which seceded from Sudan in July 2011 as part of the landmark 2005 peace deal.

Both nations have stepped up diplomatic efforts ahead of the AU summit, where the outstanding issues relating to South Sudan's independence will be discussed, including whether to adopt the proposal on Abyei put forward by the AUHIP.

On Friday, South Sudan's chief negotiator with Sudan Pa'gan Amum met the president of Equatorial Guinea, Teodoro Obiang Ngueme, in Malapo to discuss the "political and security situation between South Sudan and Sudan ahead of the awaited AU summit, as well as the Peace and Security Council (AUPSC) meeting scheduled to take place this month in Addis Ababa".

According to a statement from Amum's press team, "President Obiang gave his full support to the AUHIP proposal to resolve the final status of Abyei area and to South Sudan's position on borders demarcation."

In September, the two sides signed a number of agreements on contested borders, oil and other issues, but they have yet to be implemented on. "President Obiang", the press release said, "also echoed the call of his colleagues in neighboring countries on Sudan to honor and implement its agreements with South Sudan including the September cooperation agreement and to find a peaceful settlement to all disputes between the two countries."

Amum concluded his West African trip on Friday, having met with the Ivory Coast president, Alassane Quattra, earlier in the week to deliver a letter from South Sudan's president Salva Kiir.

Quattra requested to meet Kiir during the AU summit and "has supported the position of South Sudan to peaceful solution of the borders disputed and claimed areas, as well as the final status of Abyei area", the press release said.

In his capacity as chair of the Regional Block of West Africa countries, the Ivorian president said he would discuss the remaining outstanding issues between the Sudans with his West African counterparts "in support of the AUHIP proposals on the final status of Abyei and borders disputed and claimed areas", the statement said.