WorldView: Navalny health concerns; Iran, U.S. working groups on nuclear deal

Jailed Russian opposition leader Alexey Navalny's lawyers say he tested negative for coronavirus despite showing signs of respiratory illness. Iran and the U.S. have agreed to establish working groups to get both countries back into compliance with the 2015 nuclear deal. CBS News foreign correspondent Roxana Saberi joins "CBSN AM" with a roundup of these and other headlines.