MOSCOW (Reuters) - Britain's main suspect in the London murder of dissident Alexander Litvinenko is likely to run for mayor in the Russian city hosting the 2014 Winter Olympics, according to an announcement by his party on Friday.

The winner of the election on April 26 will be mayor of the resort town on the Black Sea for five years and have a strong influence on how to spend billions of dollars earmarked for the Winter Olympics in February 2014 which he or she will host.

The LDPR considers Andrei Konstantinovich Lugovoy as its most likely candidate in the election of the mayor of Sochi, the LDPR, a right-wing political party, said on its Web site.

British police want to arrest Lugovoy for killing Litvinenko with a radioactive poison in London in 2006, a crime that sparked one of the worst rows between Britain and Russia since the end of the Cold War.

Russia has refused to extradite Lugovoy, citing its constitution which bans handing over nationals to stand trial in foreign countries. Lugovoy, a 42-year-old member of parliament for LDPR, denies any role in Litvinenko's murder.

The previous mayor, a member of the ruling United Russia who won the last election with a large majority, resigned last year because of poor health. The acting mayor is likely to be United Russia's candidate for the April vote and to win the post.

LDPR, or Liberal Democratic Party of Russia, holds around 9 percent of the seats in the national parliament. It said Lugovoy's experience makes him an excellent candidate.

The widow of the murdered Litvinenko said his election as mayor would be an insult to fans of the Winter Olympics.

I would personally go from country to country urging people not to go to an event hosted by a murderer, Marina Litvinenko said in an emailed statement.

(Writing by James Kilner; editing by Philippa Fletcher)