South Sudan has accused Sudan of preventing it from exporting 3.4 million barrels of its crude exports and diverting oil from its refineries.

According to South Sudan, more than 500,000 barrels of oil have been diverted to Sudan’s refineries and that Sudan has built a pipeline with the intention to continue to divert oil.

South Sudan’s minister of petroleum and mining, Stephen Dhieu Dau, has said that Sudan appropriated all of South Sudan’s Nile Blend crude oil entitlements for December to refineries in El-Obeid and Khartoum.

Relations between the two countries have been tense since the south broke away from the north of the country in 2011 following a popular vote. The new states have failed to agree on the amount that South Sudan should pay to Sudan to transport its oil before shipping.