PetroChina Company Limited (PetroChina), the world's second-largest oil and gas firm, reported a $6.21 billion profit in the first quarter on Thursday, giving the company a 5.8 percent increase compared to the same period a year ago.

The company, propelled by strong oil and natural gas production gains, was able to overcome the money lost in the refining business. The total crude oil processed in the first quarter was 257.1 million barrels, which is a 2.8 percent increase compared to the same period a year ago.

The higher output for PetroChina has been the result of its fields located overseas. Its overseas production climbed 17.1 percent to 31.2 million barrels of oil equivalent in the first quarter.

It plans to invest at least $60 billion this decade in global oil and natural gas assets. In February it bought a 20 percent stake in Shell’s Groundbirch shale-gas project in British Columbia. It plans to produce 1 billion cubic meters of shale gas by 2015.

However, losses in the refining business have been eating into its profit. It has been urging the government to increase fuel prices so that the cost of crude can be, in part, passed on to the consumers.

China has increased fuel prices by 11 percent in the first quarter indicating that it wanted to help local refiners cut heavy losses. China follows a fuel pricing system in which domestic fuel prices can be regulated when there is a change of more than 4 percent over a period of 22 working days in the cost of crude.

This increase in China comes at time when oil prices are on a rise worldwide as a result of mounting global demand and also intensifying tensions between the West and Iran, which is the second-biggest producer in the Organization of the Petroleum Exporting Countries.

However, the rise in fuel prices has caused unrest in the public with inflation growing to 3.6 percent in March from a year earlier.