U.S. lawmakers are moving to block the planned visit to the U.S. of two Russian generals who they say helped cover up the murder of a Russian whistleblower in prison three years ago.

Their appeal in a letter to Secretary of State Hillary Clinton ratchets up pressure on the Obama administration, which is defending a “reset” in relations with Moscow as a major foreign-policy accomplishment. Some in Congress have been calling for a tougher line toward Moscow.

The case of the dead whistleblower, Sergei Magnitsky, has been a source of friction in Russia-U.S. relations, and the Kremlin has bristled at a visa ban that the U.S. implemented on Russian officials linked to Mr. Magnitsky’s imprisonment and death.

Moscow this summer retaliated with its own blacklist of U.S. officials, in what one Russian official derisively called “the war of the lists.” So far, neither side has actually barred an official who has tried to visit Washington or Moscow.

U.S. Sens. Roger Wicker (R., Miss.) and Benjamin Cardin (D., Md.) urged Mrs. Clinton in a letter on Monday to “immediately review any possible visa applications” submitted by two Russian Interior Ministry generals who are scheduled to enter the U.S. around Nov. 15.

Wall Street Journal