The Kremlin said on Thursday that a call by opposition leader Alexei Navalny to hold nationwide protests to back a boycott of next year’s presidential election would be investigated to see if it broke the law.

Navalny, a fierce critic of President Vladimir Putin, on Wednesday announced a series of rallies across Russia on Jan. 28 to press home his call for a boycott of the election, in which he has been barred from running.

Kremlin spokesman Dmitry Peskov said Navalny’s move would be carefully studied.

“We have the appropriate agencies that, as you know, check such calls and plans to see if they are lawful,” Peskov told a conference call with reporters. “There is no doubt that this will be done.”

Polls indicate that Putin, who has dominated Russia’s political landscape for 18 years, is on course to comfortably win re-election on March 18, but Navalny says his own exclusion makes a farce of the ballot.

An election boycott could pose a problem for the Kremlin, which is keen to ensure a high turnout in the election to help confer legitimacy on Putin’s expected victory amid some signs of apathy among voters.

Under Russian law, the time and place of public rallies must be agreed in advance with the authorities, who have often declined to authorize them in the past, citing conflicting events or security concerns.

When the opposition has gone ahead anyway, the police have broken up rallies by force and detained participants.

Navalny, who has organized some of the biggest anti-government demonstrations in years, has been jailed three times this year and charged with breaking the law for organizing public meetings and rallies.