Vladimir Putin's top critic Alexei Navalny will be able to run for president after 2028, the head of the Russian Central Election Commission said on Tuesday.
Russians are scheduled to go to polls to elect a president next March and Navalny, 41, has declared his intention to run against Putin.
In February 2017, a court found Navalny guilty of embezzlement and handed him a five-year suspended sentence.
While Navalny and his supporters say his prosecution is political, officials say the ruling makes him ineligible to run for Russia's top job.
The case dates back to 2013 and a retrial came after the European Court of Human Rights said the first trial was unfair.
Ella Pamfilova, the head of the Central Election Commission, said Navalny would be able to put his name on the ballot once his criminal record has been expunged -- "after 2028."
Speaking at a forum in the Black Sea resort of Sochi, Pamfilova said Navalny would be able to run in about 10 years and five months.
"He's got his whole life ahead of him," she was quoted as saying by Russian news agencies.
"So he should proceed from that. And good luck to him!" she added, calling him a "young, promising politician."
Putin, 65, was Russia's first elected president in 2000 and is widely expected to seek another six-year Kremlin term in the March election.
Navalny has dismissed all charges against him, accusing the authorities of seeking to sabotage his political career.
In early October a court sentenced Navalny to 20 days in jail over repeatedly violating a law on organising public meetings.
Earlier this year the charismatic Yale-educated lawyer served sentences of 15 days and 25 days for organising unauthorised anti-Putin protests.
In 2013, Navalny stood for Moscow mayor with a Western-style campaign and a message of snuffing out corruption, coming second against a Kremlin-backed incumbent.