Positive economic data from China and renewed tensions over the conflict in Syria added positive pressure to crude oil prices at the start of Thursday trading.

West Texas Intermediate, the U.S. benchmark for crude oil prices, rallied more than 3 percent above the previous close to hit $46.58 per barrel at the opening bell in New York. Brent crude oil rose 2.5 percent to $49.54 per barrel.

Crude oil prices have see-sawed on mixed economic data from major economies. The U.S. labor market continues to show signs of strength, though Europe still struggles to emerge from recession while Asian economies, notably China, show signs of a slowdown.

While still below a level indicating expansion, the Chinese manufacturing Purchasing Manager's Index of 49.8 was up a fraction of a percent from August, showing some indication the Chinese contraction may be slowing.

Beijing this year devalued the nation's currency, adjusted key interest rates and injected cash into the market in an effort to arrest the decline. The official Xinhua News Agency reports lending authorities this week cut the minimum down payment for first-time home buyers.

Geopolitical factors tied to lingering turmoil in Syria added risk to prices. Russian military forces started air campaigns in support of forces loyal to Syrian President Bashar Assad, while the United States continues to support rebel groups and combat the rise of the group calling itself the Islamic State.

White House spokesman Josh Earnest suggested in his Wednesday press conference Russia was responding from a position of weakness brought on the dual economic strains of lower crude oil prices and tighter sanctions.

"They are seeing the client state that they have maintained inside of Syria progress over the course of five years from being a relatively stable state where they could exercise significant influence to a country that's torn apart by chaos and that risks the status of the leader that they have supported there for years," he said. "That is what has prompted Russia to ramp up their involvement there."