MOSCOW - Under Soviet dictator Joseph Stalin, people who fraternized with foreigners or criticized the Kremlin were "enemies of the people" and sent to the gulag. Now, human-rights activists say legislation backed by Vladimir V. Putin's government could throw Russia back to the days of the Great Terror.

The legislation would create "a base for a totalitarian state," Lev Ponomaryov, an outspoken government critic and rights activist, contended yesterday.

Government supporters and Kremlin-allied lawmakers said the bill - submitted to the Kremlin-friendly parliament last week - would tighten up current law. Supporters say prosecutors often have trouble gaining convictions because of ambiguities in the definition of state treason.

Under the bill, the list of banned recipients of state secrets would grow to include nongovernmental organizations based anywhere in the world that have an office in Russia. The government has repeatedly accused foreign spy agencies of using NGOs as a cover to foment dissent.

Critics warned that the loose wording would give authorities ample leeway to prosecute those who cooperate with international rights groups.

Under current treason statutes, some NGOs are not considered "foreign organizations," meaning that a person who passes a state secret to an NGO might not be considered a traitor.

Some of Russia's most prominent right activists, including Moscow Helsinki Group head Lyudmila Alexeyeva and Civic Assistance director Svetlana Gannushkina, said the bill empowered authorities to prosecute anyone deemed to have "harmed the security of the Russian Federation."

It is "legislation in the spirit of Stalin and Hitler," the activists said in a joint statement - legislation that "returns the Russian justice to the times of 1920-1950s."

During the 1930s, Stalin oversaw a sweeping crackdown that came to be known as the Great Terror. Millions were accused of being "enemies of the people," convicted by farcical courts based on hearsay and anonymous allegations, and executed or sent to the vast system of prison camps known as the gulag.

The legislation expands the definition of treason to include damaging Russia's "constitutional order," and "sovereignty or territorial integrity."

The activists believe that each proposed addition cynically targets potential threats to the Kremlin, shattering what remains of civil society in Russia.

Activists said that expanding the term

constitutional order

would effectively outlaw opposition protests.

Territorial integrity

would forbid anyone from calling for independence or perhaps autonomy, an issue of particular concern in the volatile North Caucasus, where Chechnya is located.

The bill broadening the definition of state treason is the latest in a series of measures taken since Putin's rise to the presidency in 2000 that have rolled back Russia's post-Soviet political freedoms.

Rights group say that rollback has shown no signs of stopping since Putin, a former director of the KGB's main successor agency, became prime minister and his protege, Dmitry A. Medvedev, assumed the presidency.