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April 21 (Reuters) - Contract driller Nabors Industries Ltd's quarterly revenue fell 10.5 percent, hurt by slower drilling activity in North America, and the company said it had cut its workforce by more than 18 percent since the end of 2014.
Revenue from Nabors' drilling operations in the United States - the company's biggest market - fell 17 percent in the first quarter from the previous quarter with oil producers slashing budgets to combat a slide in crude oil prices.
The company reported revenue of $1.42 billion in the quarter ended March 31, compared with the analysts' average estimate of $1.34 billion, according to Thomson Reuters I/B/E/S.
While revenue from Nabors' international drilling business rose 3 percent from the previous quarter, the company forecast a 10 percent drop in international rig counts through the year.
The company said this would start hurting results later in the year, but added that it expected full-year revenue from its international business to rise.
Nabors, whose completion & production unit is merging with C&J Energy Services Ltd, also forecast lower second-quarter results due to weak drilling activity, but did not provide more details.
The company said on Tuesday it had cut its workforce by 41 percent in its U.S. drilling operations and 26 percent in Canada. It had about 29,000 employees as of Dec. 31, 2014.
Nabors' shares were up 1.3 percent in extended trading on Tuesday. Up to Tuesday's close, they have risen nearly 11 percent this year. (Reporting by Tanvi Mehta in Bengaluru; Editing by Kirti Pandey and Sayantani Ghosh)