Berezovksy, in an interview with the BBC, said he was ready to meet with Russian and British investigators if it would help find out who killed Litvinenko.
Britain has not yet agreed formally to let Russian investigators come to London to pursue leads in the case. British authorities are continuing to investigate the death.
Berezovsky also told the BBC that Litvinenko told him before his death that he suspected that Russian businessman Andrei Lugovoi was involved in his poisoning.
Lugovoi has denied playing any role in Litvinenko's fatal sickness.
Litvinenko died in London last November 23 after being poisoned with the rare radioactive isotope polonium-210.
The London-based Berezovsky was a friend and supporter of Litvinenko. Both men have been critics of Russian President Vladimir Putin's government.
(AP, AFP, BBC)