South Sudan's oil production has dropped by nearly 30 percent since mid-December last year, due to the fighting between government forces and rebels loyal to former Vice-President Riek Machar, officials said on Sunday. The country's daily oil production used to reach 245,000 barrels before the fighting broke out, but now that figure has been slashed to 175,000 barrels, said Ateny Wek Ateny, a presidential office spokesperson, at a press conference in Khartoum on Sunday. Latest reports said that South Sudanese rebels have targeted the oil-producing states of Upper Nile and Unity. They are still in control of Bantio, the capital city of Unity state where 45,000 barrels are produced a day. In Upper Nile state which has a daily yield of 200,000 barrels, Machar and government forces have been taking control the capital city Malakal in turn. According to UN reports, the fighting in South Sudan have left thousands of people dead. More than 67,000 Southern Sudanese have been displaced to neighboring countries. Also at the press conference, Mayan Dot, South Sudan's ambassador in Khartoum, said that the number of South Sudanese refugees in Sudan reached more than 12,000. The Inter-Governmental Authority for Development (IGAD), a regional organization formed by east African countries, is now mediating between South Sudanese rivals in the Ethiopian capital of Addis Ababa. But the South Sudanese government on Sunday announced that the IGAD has failed to narrow view points between the two parties regarding the political files under negotiation. According to local media in Sudan, South Sudan's government spokesman Michael Makwi said that the negotiations were still continuing in Addis Ababa under the patronage of the IGAD, but the two parties have not yet agreed on the agenda of the negotiations regarding the political files. Makwi said the negotiations were progressing very slowly, because the IGAD failed to find a mechanism for reaching an agreement on the negotiation files for the new round.