Ghazi Salaheddin from President Omar Hassan al-Bashir's National Congress Party (NCP) criticised the law governing the 2011 referendum passed in December after months of wrangling, saying it lacked any deadline to address outstanding problems.
"Imagine if we had the referendum and separation happened and we had not yet agreed on the borders? This is war," he told the small state-owned Blue Nile television, according to a transcript seen by Reuters on Tuesday.
Most of Sudan's oil fields traverse the north-south border which has yet to be demarcated. Sudan's external debt is about $30 billion.
Salaheddin said hundreds of thousands of southerners in the north and northerners living in the south would be left in limbo if their nationalities were not defined.
He also warned of regional problems over what international agreements would be respected by a separate south, giving the example of an agreement over Nile waters with Egypt.
"The government cannot go ahead with this referendum until some of these issues have been discussed," he said.
"It is (now) possible that the ... southerners could vote for separation without us having settled the issues of the border, nationality and international agreements and this is a prescription for war," he said.
The southern former rebel Sudan People's Liberation Movement (SPLM), which signed a 2005 north-south agreement sharing wealth and power, called Sahaleddin hostile and said he wanted to rewrite the peace deal.
"If you make these things conditions for the referendum then it will never come," Atem Garang, the SPLM's deputy speaker of parliament, told Reuters.
He said some key issues like the border could be decided before the 2011 vote, but a six-month period after any vote for secession had been set aside to discuss outstanding problems.
Fought over issues including religion, ethnicity, ideology and oil, a north-south civil war that began in 1983 claimed an estimated 2 million lives and drove 4 million from their homes, destabilising much of east Africa.
Five years of stalling in implementing the 2005 peace deal has fuelled distrust between the NCP and SPLM and many fear a return to war if there is a hint of malpractice during the referendum. (Writing by Opheera McDoom; editing by Andrew Roche)
- Reuters - Thomson Reuters Foundation
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