Oil prices fell for a sixth day today after Iran announced plans to boost production and U.S. crude output hit record highs, adding to concerns about a sharp rise in global supplies. Brent futures were down 49 cents or 0.76 percent, at 64.32 dollar when report last came in. Yesterday Brent fell 1.1 percent to its lowest close since 20th December.U.S. West Texas Intermediate, WTI, crude was down 68 cents, or 1.11 percent, at 60.47 dollar a barrel. In the previous session, it was down 1 percent at its lowest close since 2nd last month.