Citigroup downgrades PetroChina from Hold to Sell, saying an earnings disappointment is coming. Citi reduced PetroChina's earnings per share estimate for 2008 by 15.4 percent and for 2009 by 5.5 percent.

We cut our FY08 and FY09 EPS estimates by 15.4% and 5.5% respectively in line with our global increase in oil price Estimate change estimates. While higher oil prices will drive higher E&P division earnings we expect this to be more than offset by higher losses in PetroChina's refining division. We are now using an average Brent oil price of $96/b and $88/b for FY08 and FY09 respectively (FY07 was $72/b), said Citi analyst Graham Cunningham in a note to investors.

The Hong Kong-listed arm of PetroChina dropped 2.7 percent to HK$9.98 as oil prices surged.