The Luxembourg Boxing Federation has begun legal proceedings against the British Boxing Board of Control in a row over this month's bout between David Haye and Dereck Chisora.
Neither man has a licence from the BBBofC but the LBF sanctioned the fight, which is due to take place at Upton Park next Saturday, July 14.
The BBBofC have threatened to rescind the existing licences of anybody involved in the promotion of the fight, but the LBF have today responded.
In a statement, they said: "[Legal action] is not something anyone wanted to do and neither is it a step we took lightly, but we felt we were left with no option.
"We have issued proceedings to prevent the Board from intimidating its own members into not participating in the fight.
"The Board has admitted that it can do nothing legally to stop the fight but it is still threatening to call its licence-holders to account for their involvement."
The fight will be shown on BoxNation in the UK.
