Sudanese presidential assistant Nafie Ali Nafie has accused South Sudan's negotiators of scheming to overthrow Sudan's government.

Nafie made the allegation following a meeting Wednesday with a visiting Norwegian delegation led by Minister of Environment Erik Solheim.

The Norwegian group was in Africa to try to smooth over the developing crises between the two countries.

Nafie did say Sudan wouldn't hesitate to respond to any initiative from South Sudan aimed at seeking a solution to the impasse over oil and guerrilla fighting issues.

He added, however, that negotiations with South Sudan couldn't proceed unless the South Sudanese government replaces its negotiating team, The Sudan Tribune reported Thursday.

Representatives of the countries have been meeting in Ethiopia regarding outstanding disputes, which include clashes in states that line the new international border.

Relations have been tense since South Sudan seceded from Sudan last July following a vote early last year in which people in the southern sections of the country overwhelmingly voted to form their own country.

Even before that oil was seen as a potential sticking out.

Since then, however, the two nations have been at loggerheads over several points; but most pointedly over oil. Most of the oil in the region is in South Sudan but all the export infrastructure is in Sudan.

South Sudan last month halted oil production to protest Sudan's confiscation of South Sudan's shipments the commodity across its territory.

Sudanese officials have accused South Sudan of seeking to topple the government in Khartoum through economic pressure by stopping oil production.

Disputed transit fees are causing gridlock between the countries. South Sudan has proposed paying up to $1 per barrel tariff to use Sudan's pipelines, while Sudan insisted on a $32.20 per barrel tariff.

South Sudanese officials declared force majeure on loading supplies of Nile and Dar Blend crude into pipelines, shutting down exports.

The issue has international overtones as well, as China depends on the Sudanese states for roughly 5 percent of its oil imports, buying about 365,000 barrels per day of the 500,000 bpd production overall in the region. That ranks seventh among China's oil suppliers.

The next round of talks between Sudan and South Sudan is scheduled for March 6 but the negotiating positions of Khartoum and Juba appear gridlocked.

Sudan maintains that South Sudan must agree to pay $36 per barrel of oil exported through its pipelines. While South Sudan rejects the amount, it has offered to pay $2.6 billion to Sudan and forgive Khartoum's debt of $2.8 billion as compensation.