Boris Berezovsky said he had "no regrets" about taking his case against Roman Abramovich to court.
He said he did "not understand what happened" in court today and that he "needs to analyse on what happened".
Boris Berezovsky said he was "absolutely amazed" and "surprised completely" by today's ruling, outside the High Court.
He added that Mrs Justice Gloster tried to "re-write Russian history".
Boris Berezovsky looked impassive when the judge went through her reasons.
The judge described Berezovsky as an "unimpressive" and "unreliable" witness who at times clearly made up his evidence.
Abramovich on the other hand was "truthful" and on the whole a "reliable" witness.
Mrs Justice Gloster announced in a summary of her judgment:
When announcing that Russian oligarch Boris Berezovsky had lost his High Court battle,Mrs Justice Gloster said she found Mr Abramovich "to be a truthful, and on the whole reliable, witness".
Russian oligarch Boris Berezovsky has lost his High Court battle with Roman Abramovich.
Mr Berezovsky, 66, was seeking more than £3 billion damages after accusing the 45-year-old Chelsea football club owner of blackmail, breach of trust and breach of contract. Mr Abramovich denied the allegations.
Mrs Justice Gloster ruled in Mr Abramovich's favour after a trial in London which started in October 2011 and ended in January this year.
Russian billionaires Roman Abramovich and Boris Berezovsky encountered one another when they arrived at court last October.
Mr Berezovsky has claimed more than £3 billion in damages against the Chelsea owner in the biggest private litigation battle in legal history.