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WASHINGTON, Jan 16 (Reuters) - Legislation to keep sanctions in place on companies that have been controlled by the Russian oligarch Oleg Deripaska, including the giant aluminum firm Rusal , stalled in the U.S. Senate on Wednesday, a victory for President Donald Trump.
The vote was 57-42 to end debate on the measure, as 11 of Trump's fellow Republicans joined Democrats in favor of the resolution, amid questions about Trump's relationship with Moscow.
That result fell short of the 60 votes necessary to advance to a final passage vote in the 100-member Senate, where Republicans have a 53-47 seat majority.
Similar legislation has been introduced in the Democratic-led House of Representatives, but the resolution's fate was uncertain. To go into effect, the measure must pass the Senate and House and survive an expected Trump veto.
Many members of Congress have been questioning the U.S. Treasury Department's decision in December to ease sanctions on the core businesses of Deripaska - Rusal, its parent, En+, and power firm EuroSibEnergo - watering down the toughest penalties imposed on Russian entities since Moscow's 2014 annexation of Crimea from Ukraine. Deripaska himself remained subject to U.S. sanctions.
The Trump administration pushed Republican lawmakers not to support the resolution introduced by Senate Democratic Leader Chuck Schumer, which would have prevented the administration from lifting the sanctions.
Senate aides said Treasury officials had approached senators and staff repeatedly in recent days to argue that it was appropriate to lift the sanctions imposed in April because Deripaska had agreed to cut back his controlling stakes.
European countries had also lobbied for the sanctions to be eased.
Democrats had been optimistic they would get 60 votes on Wednesday, after 11 Republicans made the unusual break from Trump policies and supported the resolution in procedural voting on Tuesday.
Schumer said the measure was necessary to send a message to Russian President Vladimir Putin after actions such as aggression in Ukraine and the finding by U.S. intelligence that Moscow interfered in the 2016 U.S. election to boost Trump.
"What's (Putin) going to do next? What's he going to ask President Trump to do next, and what will Trump do?" Schumer asked in a Senate speech before Wednesday's vote.
But the Senate's Republican majority leader, Mitch McConnell, dismissed the resolution as a political stunt. Republicans who voted against it said Deripaska had done enough by reduced his stakes in the companies.
(Reporting by Patricia Zengerle Editing by Susan Thomas and Bernadette Baum)