Europe's largest oil company Royal Dutch Shell PLC reported a 57 percent increase in net profit for the first quarter on Wednesday due to higher oil prices and its first substantial production increase in years, the Associated Press reported. Net profit was $5.48 billion, up from $3.49 billion in the same period a year ago. Revenues were $86.0 billion from $52.2 billion. Oil production increased 6 percent from the first quarter of 2009 to 3.59 million barrels of oil per day _ a positive surprise, since Shell had said production would be flat this year. «So far in 2010, oil prices have remained firm, and demand for petrochemicals has increased, but refining margins, oil products demand and spot gas prices all remain under pressure,» Chief Executive Peter Voser said in a statement. «Although there are signs of an improving economic outlook, we are not relying on it, we are continuing with our focus on cash flow growth, underpinned by new project startups and lower costs.»