Russia's parliament has given tentative approval to legislation that, if passed, would expand the definition of high treason.
Rights activists said it could be part of a widening crackdown on dissent.
The current law equates high treason to espionage.
Under the new bill, treason would include activities such as financial or consultative assistance to a foreign state or organization.
The current law describes high treason as activities harming Russia's external security.
The new legislation would widen the definition to include moves against Russia's constitutional order, sovereignty and territorial integrity.
The State Duma unanimously approved the bill on September 21 in the first of three required readings.
Lyudmila Alekseyeva of the Moscow Helsinki Group said it was aimed at "ending any independent public activism."
Veteran rights activist Lev Ponomaryov said it could be used to prosecute critics of the government.
Based on reporting by AP, ITAR-TASS, and Interfax