A move to ban members of “extremist” organizations from running for office passed the first round of parliamentary discussions in Russia on Tuesday. The move is seen by critics of the Kremlin as an attempt to stop prominent opposition from running against Russian President Vladimir Putin.

The bill was supported by 293 MPs, primarily from the United Party, of which Putin is the de facto leader. The draft law still needs to pass through two more readings in the lower house before heading to the upper house, and then be signed into law by Putin.

If passed, opposition campaigns would likely be derailed or otherwise forced to discontinue. Lyubov Sobol, an activist currently under house arrest for protesting in favor of jailed opposition leader Alexei Navalny, describes the bill as “unconstitutional” and an attempt to bar her from running in the September elections.

Vasily Piskarev, co-author of the bill, said the legislation is necessary to bar people from “extremist” organizations from sitting in Parliament because they could use their position “for propaganda and the justification of their ideas.”

While the bill is making its way through the Russian Parliament, a Russian court is separately considering whether the political operations of Navalny and his supporters are eligible for the “extremist” designation in a high-profile case against Navalny.

Under current Russian law, the determining factor in qualifying a group’s activity as “extremist” is intention. Under section 282.1(2) of the Russian Criminal Code, “crimes committed on the grounds of political, ideological, racial, national or religious hatred or enmity … against a social group” fall within the classification.

If the court applies the designation, Russian authorities will gain the formal power to jail persons associated with the group and freeze the organization’s bank accounts.

Navalny’s Anti-Corruption Fund, already deemed a “foreign agent” by the Russian Minister of Justice, and Navalny’s support network have hastened their dismantling as a result. Leonid Volkov, a prominent Navalny supporter, previously stated that “it is impossible to work under these conditions.” The Fund was ordered to suspend their operations by the court while the case proceeded.

The Russian Constitution guarantees basic human rights including freedom of expression and association; at the same time, Article 13 prohibits public associations aimed at changing the integrity of the Russian Federation. However, the terms “extremist” and “extremism” are not used.

The next court hearing is slated for June 9.