Bout from Russia is escorted by a member of the special police unit as he arrives at a criminal court in Bangkok
Alleged arms smuggler Viktor Bout from Russia is escorted by a member of the special police unit as he arrives at a criminal court in Bangkok October 4, 2010. Reuters

Viktor Bout, the Russian arms dealer freed on Thursday after 14 years in U.S. custody in exchange for U.S. basketball star Brittney Griner, has joined the Kremlin-loyal ultranationalist Liberal Democratic Party (LDPR), its leader said on Monday.

In a video posted on Telegram, LDPR leader Leonid Slutsky, standing on a stage beside Bout, said: "I want to thank Viktor Anatolievich (Bout) for the decision he has made and welcome him into the ranks of the best political party in today's Russia."

Despite its name, the Liberal Democratic Party (LDPR) has since its founding in 1991 espoused a hardline, ultranationalist ideology, demanding Russia reconquer the countries of the former Soviet Union.

Its founder and long-time leader Vladimir Zhirinovsky gained a reputation as a political showman for his outrageous stunts and eccentric behaviour before his death in April.

Though seen as a serious contender for power in the 1990s, the LDPR has since assumed a subordinate role in Russia's political system, providing token opposition to the ruling United Russia bloc while backing the Kremlin on most issues.

It has a history of recruiting controversial personalities into Russian politics. In 2007, Andrei Lugovoy, a former KGB agent wanted in Britain for the murder the previous year of Russian ex-spy Alexander Litvinenko was elected to parliament for the LDPR.