The RUSSPR (Russian Revolutionary Socialist Party) has announced it is now officially a political party, after the Russian parliament approved it for the first time in September.
The party, which has about 30 million members nationwide, was founded by Alexander Borodai, a political scientist who was once a close ally of Vladimir Putin.
His party is backed by about 40% of the Russian population, with many others supporting the new political party.
The first official Russian presidential election will take place on 8 October, and the Russian constitution allows a presidential term of five years, with the leader being elected by popular vote.
The constitution also gives Putin full power to appoint ministers, who would then be sworn in by the president.
The election will be held on 7 October, with candidates on all 50 seats of the country’s parliament, with a third party also expected to enter the race.
Borodais was arrested in February, and a court later ordered his arrest.
“I am not a criminal,” Borodaei told RIA Novosti news agency.
“If I were to be jailed for any reason, I would fight it and try to defend myself.”
Borodiai was arrested after he went to a meeting of the RUSSEP in St Petersburg, where his supporters were gathered.
“The party has no formal political party designation,” Borodais lawyer Vadim Mikhalevich told Reuters news agency in a statement.
“It has always been a party of independent activists who are interested in promoting their own political interests.”
He added that “Borodai’s arrest and the party’s establishment of a formal political status means that the RUSTO (Russian Federation of Revolutionary Socialist Organisations) has become a political institution.”
The party is currently run by two former members of the Soviet-era Communist Party, Nikolai Bukharin and Mikhail Pashinyan.
They will be joined by Borodaeai, who will become a deputy head of the party.
Borodai is the first former member of the Communist Party to be elected as a member of parliament, and he is a founding member of his party’s new national council.
“We will fight the ruling regime and its puppet state and will defend our republic,” Borodonai said.
The RUSTOP, a former Soviet-style political party which had close ties to the Soviet Union, is one of the most influential in Russia and was founded in 1928.
It has been criticised by some as a far-right party and as a threat to the rule of law, which it says was put in place to safeguard the interests of the working class and oppressed people.
RUSTOPS first came to prominence in the Soviet era, when it was a major political party in the 1920s and 30s.
It was the main political force in the Russian Federation during the period of Lenin’s rule, which was the second half of the 20th century.
Borodonaei is expected to join the party and take part in its national council as the group’s leader, while Borodais former party colleague and current party deputy Nikolai Sukhodko will become the new deputy head.
He is also expected hold an influential role within the party as its secretary.
The new party, RUSTPO, is not the first to join Russia’s ruling government.
The United Russia party, the largest opposition party in Russia, joined the Russian government in February 2018.
It is supported by the ruling Liberal Democratic Party, which is led by Vladimir Putin, as well as the Social Democratic Party.
The ruling United Russia Party is expected take part as the ruling party in a new national election on 7 November.