US warns of 'consequences' if Putin critic Navalny dies as doctors raise health concerns

US National Security Advisor Jake Sullivan warned Sunday that Russia will face "consequences" if hunger-striking Kremlin critic Alexei Navalny dies.

US National Security Advisor Jake Sullivan warned Sunday that Russia will face "consequences" if hunger-striking Kremlin critic Alexei Navalny dies. Jailed opposition leader Navalny, President Vladimir Putin's most prominent opponent, was arrested in January upon returning to Russia after recovering from a near-fatal poisoning attack he says was orchestrated by Moscow. "In terms of the specific measures we would undertake, we are looking at a variety of different costs that we would impose, and I'm not going to telegraph that publicly at this point," Sullivan told CNN.