World oil prices advanced yesterday following data that showed US oil companies cut drilling activity in response to low prices. US benchmark West Texas Intermediate for March delivery gained 1.33 US dollars to close at 49.57 US dollars a barrel on the New York Mercantile Exchange. European benchmark Brent oil for March delivery jumped 1.76 US dollars to 54.75 US dollars a barrel in London. Traders were also watching a strike at nine US refineries after labour negotiations broke down between union leaders and refiners. The strike pushed up gasoline prices by about nine per cent since Friday on worries of constrained refined products supply.