Aug 20 (Reuters) - The government of Canada's main oil-producing province, Alberta, said on Tuesday it was extending mandatory curtailments on crude production by an extra year through 2020, due to uncertainty about when expanded pipelines may come online.

HOUSTON (Reuters) - Two U.S. shale producers have challenged an energy pipeline operator's proposed surcharge for the Trump administration's 25% tariff on imported steel, raising the stakes for pipeline builders facing higher construction costs.

(Reuters) - Canadian environmental groups fear losing their tax-free charity status if they run paid climate change advocacy adverts ahead of the October national election, after a warning from the federal election watchdog.

(Reuters) - Teva Pharmaceutical Industries Ltd on Tuesday made its generic version of Mylan's EpiPen for young children available in most retail pharmacies at $300 for a 2-pack.

BIARRITZ, France (Reuters) - The French seaside resort of Biarritz will be transformed into more of a fortress than a surfers' paradise as organizers of this weekend's G7 summit prepare to shield world leaders from outside disturbances.

BIARRITZ, France, Aug 20 (Reuters) - The French seaside resort of Biarritz will be transformed into more of a fortress than a surfers' paradise as organizers of this weekend's G7 summit prepare to shield world leaders from outside disturbances.

(Reuters) - Canada's 11-times canoe world champion Laurence Vincent Lapointe maintained she is not a drug cheat on Tuesday but conceded there will be people who will never believe her.

Aug 20 (Reuters) - Canada's 11-times canoe world champion Laurence Vincent Lapointe maintained she is not a drug cheat on Tuesday but conceded there will be people who will never believe her.

CHICAGO (Reuters) - United States Steel Corp will temporarily lay off hundreds of workers at its Great Lakes facility in Michigan in coming weeks, according to a filing the steelmaker made with the State of Michigan.