WASHINGTON (Reuters) – The leaders of the U.S. Senate Foreign Relations Committee asked President Donald Trump on Wednesday to consider whether the Russian government poisoned Russian opposition politician Alexei Navalny with a chemical nerve agent, which would subject Moscow to sanctions.

“We are very concerned by assessments that Russian anti-corruption activist Alexei Navalny was poisoned in August 2020, by a chemical nerve agent from the Novichok family,” the committee’s Republican chairman, Senator Jim Risch, and its Democratic ranking member, Senator Bob Menendez, wrote in a letter to Trump.

The request – which followed a similar request from leaders of the House of Representatives Foreign Affairs Committee on Sept. 8 – added to growing international support for a response to Navalny’s poisoning. German Chancellor Angela Merkel said earlier on Wednesday her country would discuss a response with European partners.

The Kremlin critic was discharged from Berlin’s Charite hospital last week following 32 days of treatment after falling ill on a Russian domestic flight. Germany says he was poisoned with a Soviet-style Novichok nerve agent. Moscow has said it has seen no evidence that Navalny was poisoned.

The White House did not immediately respond to a request for comment on the letter from Risch and Menendez. The deputy U.S. ambassador to the United Nations, Cherith Norman-Chalet, told the U.N. Security Council earlier this month that it would work with allies to hold accountable those responsible for poisoning Navalny.

(Reporting by Patricia Zengerle, Editing by Rosalba O’Brien)

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