Oil prices weakened today, dampened by concerns that a recovery in U.S. demand may be slower than expected and as stockpiles of refined products continued to rise.

By midday in Europe, benchmark crude for October delivery was down 67 cents to $71.80 a barrel in electronic trading on the New York Mercantile Exchange. The contract fell 3 cents to settle at $72.47 on Thursday.

Victor Shum, an energy analyst with consultancy Purvin & Gertz in Singapore, said oil prices were held back by a slide in regional stock markets and a stronger U.S. dollar.

U.S. government data also indicating that economic recovery would be slow, which may mean less demand for energy in the near term by the world's largest crude user.

"There is a supply overhang in both crude oil and products. Oil pricing at a $70 plus level is quite vulnerable given the weak fundamentals," Shum said.