UPDATE 1-Sulzer says freed of U.S. sanctions, business as usual

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ZURICH, April 12 (Reuters) - Swiss pumpmaker Sulzer is free of U.S. sanctions after authorities approved its buyback of shares that has reduced Russian oligarch Viktor Vekselberg's stake to less than 50 percent, it said on Thursday.

"Sulzer confirms that it is no longer a blocked party or subject to sanctions under U.S. law. The company can now resume normal operations globally. To the extent that its assets have been blocked, Sulzer is taking the necessary steps to achieve timely reversal," it said in a statement.

Sulzer's U.S. bank accounts were frozen for certain transactions after sanctions were levied last week against Vekselberg and other oligarchs close to Russian President Vladimir Putin as punishment for alleged Russian meddling in the 2016 U.S. election and other "malign activity".

Sulzer's shares had tumbled by more than a fifth after the U.S. measures emerged, prompting big Swiss banks to stop trading its securities and raising the threat that Sulzer shares could be removed from major indices.

Sulzer said the U.S. Department of the Treasury's Office of Foreign Assets Control had on Wednesday authorised its plan to buy back shares from Vekselberg's Renova investment vehicle.

"This share transfer has been completed and Renova is now a minority shareholder, holding 48.83 percent of the shares in Sulzer. Sulzer now holds 15.24 percent of its own shares," it added.

"The business activities of Sulzer have been considerably disrupted, but the company does not believe that its long-term performance will be affected," it said. (Reporting by Michael Shields; editing by Brenna Hughes Neghaiwi)