N’DJAMENA - Chad’s President Idriss Deby sacked two senior ministers after a joint-venture refinery deal with China National Petroleum went sour, according to a presidential decree announced over state radio late on Friday. The oil-producer nation last week said it suspended the refinery accord after the government and CNPC failed to agree on a price of fuel coming out of the 20,000 bpd plant, which has been temporarily closed due to financial losses only months after its inauguration. The row threatens to cool relations with China.