Two weeks ago Hearn announced that he had asked for a judicial review in to the London Legacy Development Corporation's (LLDC) decision to name West Ham as their preferred tenant for the ?429million London 2012 stadium.
The Leyton Orient chairman thinks West Ham have broken the rules in their bid because they have not given his club the chance to discuss the possibility of a groundshare between the two neighbours.
Hearn thinks West Ham moving in to the Olympic Stadium will "crush" Leyton Orient because of the 60,000-seater arena's proximity to Brisbane Road, which holds just over 9,000.
Hearn has repeatedly insisted he will not back down in his long-running battle with the Hammers over the stadium, but on Wednesday he relented, admitting he will not take his legal fight any further if he is not successful in his application for a judicial review.
"If I lose the judicial review, I have got to walk (away)," Hearn told a press conference at the Nolan Partners Sport Industry Breakfast Club in London.
"That's it. It must stop - I can't do anything else. I have fought a really good fight. I've cost people a lot of money and spent a lot of money myself but I don't regret it because I think I am in the right."
Hearn is convinced he will win the judicial review, but he is not confident of being given the chance to share the stadium with West Ham if the LLDC have to start the bidding process all over again for a third time. For that reason the 64-year-old businessman has already started looking at other sites for a new ground for his npower League One club.
"If I stay (at Brisbane Road), I get crushed," Hearn added. "And I am not prepared to see a club that is 130 years old, that reaches more kids than another other in the country through the community schemes, get crushed.
"I don't know where (Leyton Orient would move to). Harlow has been mooted, Romford has been mooted, off the A13 down by the Docks... Barking way."
Source: PA
Source: PA