OREANDA-NEWS. June 16, 2011. Bank of America Merrill Lynch analysts on Wednesday upgraded PetroChina Co. Ltd. to buy. Analyst Thomas Wong said Southern Sudan's independence scheduled for July 9 may prompt PetroChina's parent, China National Petroleum Corp., to inject up to 3.4 billion of its oil reserves in the country into PetroChina.

The additional reserves could represent up to a 30% boost in proven reserves for PetroChina, he said. Wong also said sanctions against Sudan may be lifted by the international community. "With the enacting of a peace settlement, we believe there is a good chance that Southern Sudan might be taken out from the (sanctions) list, thus resuming investors' interest in PetroChina," Wong said in a note to clients.