THE HAGUE, Netherlands ( TheStreet) -- Royal Dutch Shell ( RDS.A) said second-quarter earnings rose 15% to $4.39 billion on cost savings and an increase in oil and gas production. Shell, Europe's biggest oil company, said second-quarter revenue rose to $90.57 billion from $63.88 billion. "We are delivering on our strategy," said CEO Peter Voser, in a statement Thursday. He added: "This is a good performance from Shell, despite today's challenging macro economic conditions. We are on track for growth." Shell said second-quarter production rose 5% from the year-earlier quarter to 3.11 million barrels of oil a day. Sales of liquified natural gas rose by 34% to 3.88 million tonnes. Shell said the price it receives for its oil rose 41% in the second quarter while gas prices were up 15%. Shell also said it completed a major corporate restructuring six months ahead of schedule, resulting in savings of more than $3.5 billion a year. The company said the cost-cutting measures would reduce its staff by 7,000, 18 months earlier than planned. "We continue to see mixed signals in the global economy," Voser said. "Oil prices have remained firm so far this year, but refining margins, oil products demand and natural gas spot prices all remain under pressure. Our earnings and cash flow have rallied from 2009's lows, but the outlook remains uncertain." -- Reported by Joseph Woelfel in New York. Get more stock ideas and investing advice on our sister site, Stockpickr.com.