(Bloomberg) -- Niger said five of its oil workers are being held in Benin, deepening a spat between the two African nations over the export of crude.

The Nigerien nationals, who worked for the local affiliate of China National Petroleum Corp., were at Benin’s Sèmè Kpodji port to control the loading of crude for export, the ruling junta known as Council for the Safeguarding of the Homeland, said in a statement late Saturday.

“Niger intends to take all measures to obtain the unconditional release of its citizens taken hostage, defend its rights and preserve its vital interests,” it said in the statement. 

A Benin government spokesman declined to comment. Benin’s special prosecutor said on June 5 that it had arrested five Nigerien officials at the port after they failed to properly identify themselves.

The incident comes days after Benin agreed to let Niger resume exports of crude through its port, following an intervention from China to mediate a dispute between the two West African neighbors. Landlocked Niger relies on an export terminal in Benin to ship its oil through a 1,200-mile (1,930-kilometer) pipeline from the Agadem field, which is operated by China National Petroleum Corp. 

Among those detained is the deputy general manager of West African Pipeline Company Niger, the local affiliate of CNPC, according to the statement. The company couldn’t be reached for comment when contacted outside office hours. 

CNPC holds a 57% interest in the crude production from the Agadem field. A unit of Taiwan’s CPC holds about 18%, with the remaining 25% stake owned by the government of Niger, which was taken over by a military junta last July.

The pipeline has a production capacity of 90,000 barrels a day, which is expected to reach 110,000 barrels a day once full operational.

The dispute between the two nations escalated when Niger closed its border to Benin after trade sanctions imposed by the West African regional bloc, the Economic Community of West African States, following the July coup. The ruling junta has kept the border closed for goods coming and going from Benin despite the sanctions being lifted earlier this year. 

©2024 Bloomberg L.P.