Oil prices rose on speculation that central banks will take more steps to boost growth, after manufacturing unexpectedly contracted in China.

China's Purchasing Managers Index shrank for the first time in nine months in August, a government survey showed over the weekend. China is the world's second-largest oil-consuming country after the United States.

"The disappointing data from China emphasizes that waiting for central bank action is the name of the game," said Carsten Fritsch, an analyst at Commerzbank AG in Frankfurt who predicts prices will stay above $90 a barrel this month.

"Speculation of central bank intervention will keep prices supported despite bearish fundamentals of weak demand and abundant supplies."