Navalny, Putin’s most ardent political foe, was arrested in January upon returning from Germany.
Navalny has been protesting prison officials' refusal to provide him medical care.
The opposition leader's team called for the unsanctioned demonstrations after reports that his health is deteriorating and his life was in danger.
The Russian opposition leader has been on a hunger strike since March 31 to protest the inadequate medical care he's received in prison.
The announcement comes two days after Navalny’s physician said his health was deteriorating rapidly.
“Alexei is dying... it's a question of days,” said a representative.
He says he's suffering from a lack of medical care and guard-enforced sleep deprivation.
Biden administration officials did not immediately identify the Russian officials targeted by the sanctions.
A dinosaur valentine, Texas snowstorms, and a Trump implosion round out the best images.
History will remember Vladimir Putin as "the Underpants Poisoner," the Russian opposition leader predicted.