Conoco broke a trend and raised crude oil prices.

Conoco Inc., a unit of DuPont Co., said it raised its price for West Texas Intermediate crude by $1.55 a barrel to $26.75, effective March 1. The price increase is the first by a major oil company in several months and reverses a long period of price cuts in the industry. Conoco’s prices have been the lowest among major firms and even after the increase will be below the industry average.