Sudan’s Foreign Ministry said on March 21 it has summoned Egypt’s ambassador to Khartoum, Hossam Issa, over Egypt offering oil and gas exploration blocks “in Red Sea areas subject to Sudanese sovereignty.”

It also urged oil and gas exploration companies against submitting any bids.

Egypt’s South Valley Egyptian Petroleum Holding Co has offered 10 oil and gas exploration blocks in the Red Sea for sale through a tender on March 10, with bids due to close on Aug. 1.

The Halayeb triangle, which is controlled by Egypt, has been claimed by Sudan since the 1950s. Cairo says it is Egyptian territory and it has long been a source of contention between the two neighbors.

Foreign Ministry Undersecretary Badreddin Abdullah expressed Sudan’s protest at the offer and called on Egypt “not to proceed in this direction that contradicts the legal status of the Halayeb triangle,” the ministry said in a statement.

On March 20, Saad al-Deen Hussein al-Bishri, minister of state at Khartoum’s Oil Ministry, said that offering four of the 10 blocks and other unnamed ones "within Sudanese lands in the Halayeb area ... are considered a direct intrusion into the authorities of the Sudanese Oil and Gas Ministry in granting licenses for oil and gas exploration in that area.”

“It is considered an illegal operation that carries legal consequences which will be borne by the entities carrying out this operation,” al-Bishri was cited as saying by Sudan's state news agency SUNA on March 20.

Sudan’s Foreign Ministry “warns companies operating in the field of oil and gas exploration against submitting any bids in the mentioned area,” it said in the statement on Thursday.

It said Sudan “renews the invitation extended to brotherly Egypt to use peaceful means to end this border dispute.”