KHARTOUM, July 6 (Reuters) - An internationally brokered peace deal that was supposed to transform Sudan into a unified democracy could be about to split Africa's largest country into two one-party states.
In six months time, people from Sudan's oil-producing south are due to vote in a referendum on whether they should secede and form Africa's newest nation -- a plebiscite promised under a 2005 accord that ended decades of north-south civil war.
Most analysts say south Sudan's poverty-stricken population, traumatised by the conflict and years of perceived northern exploitation, are likely to vote 'yes' for independence.
Many are already looking beyond the referendum to work out what an independent south -- and a newly separated north -- might look like. The political prognosis is not good, particularly following elections in April when opposition groups say the main northern and southern parties stamped out competition with intimidation and fraud.
Campaign group Human Rights Watch said it collected reports of harassment, arbitrary arrests and attacks on opposition figures, activists and journalists during and since the elections on both sides of the north-south border.
"The actions of the two main parties (in the north and the south) do not bode well for democratic governance after the referendum," said group researcher Tiseke Kasambala.
The domination of the two main parties was confirmed in the April elections -- the north's National Congress Party (NCP), led by president Omar Hassan al-Bashir, took most seats in Khartoum's national assembly while the south's Sudan People's Liberation Movement (SPLM), won almost every seat in the semi-autonomous southern parliament.
Both parties last month strengthened their hold still further when they announced new cabinets in Khartoum and the southern capital Juba including only a handful of largely token opposition voices.
The results came as a reality check to the ambitions set out in the 2005 Comprehensive Peace Agreement.
Under the accord witnessed by Washington, London and other powers, both sides promised to campaign to make unity attractive to their populations and to bring about the "democratic transformation" of Sudan through elections and reforms.
"Sudan is now better classified as a two-party state where democracy takes a back seat to the authoritarian regimes that control their respective regions. Opposition parties throughout the entire country now hold less than five percent of the seats in the National Assembly," academic Marc Gustafson wrote in an analysis of the results on the blog Making Sense of Sudan.
If all goes as expected in the referendum, that two-party state would become two one-party states.
Both parties say their election victories, were built on genuine popular support. "The cabinet was formed according to the result of the election," said NCP official Rabie Abdelati.
"The majority of southerners are convinced that it was the SPLM that brought them the referendum. It is the only organisation that can take them to the referendum," said senior SPLM official Yasir Arman. He said the party was investigating reports of abuses and did lose a number of seats to opposition figures in the poll.
But opposition parties say the poll was rigged. "They are not interested (in sharing power). In particular the NCP. Both of them, they are looking after their own interests," said vice president of the opposition Umma group Fadlalla Burma Nasir.
There is more at stake than the principle of multi-party politics. There are also implications for the security of the country and the surrounding region.
Sudan has long been plagued by rebellions and civil conflicts, most of them launched by marginalised groups in the country's peripheries -- most recently Darfur in the west -- challenging the dominance of the central power. Many of those fights have spread to destabilise Sudan's neighbours and disrupted companies working in the oil sector.
Oil could be one of the main flashpoints after a north-south split. Most of Sudan's proven oil reserves are found in the south, but are funnelled through northern pipelines to reach Port Sudan on the Red Sea. Northern and southern leaders have still not reached an agreement on how revenues would be divided.
Both parties will have to make serious reforms in they want to avoid a repeat of the conflicts of the past, said Fouad Hikmat of the International Crisis Group
"They (the NCP and the SPLM) have to look into political pluralism ... There needs to be serious political reform in the north and the south if they want to be stable."
And stability is no small thing for a country possibly heading towards separation. The historical precedents are far from encouraging.
"In history there are so many examples of the separation of a united country resulting in war," said Ibrahim el-Senoussi of the Islamist opposition Popular Congress Party, whose leader was released from a six-week detention last week.
"Pakistan and India and Bangladesh, Eritrea and Ethiopia and other countries. The same is going to be repeated." (Editing by Giles Elgood)