Allegations of misconduct by managers in England must be backed up with the prompt full provision of all the evidence, the LMA have said.
The League Managers Association (LMA) remains "very concerned" by allegations made in The Daily Telegraph but is "disappointed" the newspaper has still not provided the Football Association (FA) with all the requested documentation, urging them to speed up the process.
Sam Allardyce's 67-day tenure as England manager came to an end by mutual agreement on Tuesday, less than 24 hours after the Telegraph published footage claiming to be from a meeting in August between a pair of undercover reporters and the 61-year-old.
In the footage, Allardyce allegedly told two men purporting to be from a Far East investment firm how they might "get around" FA regulations concerning the transfers of players under third-party ownership.
The Telegraph has also alleged eight current or former Premier League managers stand accused of receiving illegal payments or 'bungs' as part of player transfers.
The Premier League, the FA and the English Football League then vowed to investigate after further allegations of improper transfer conduct involving coaches in the Championship were reported.
Full disclosure has now been demanded by the LMA, who feel the evidence has not been handed over to the FA quickly enough.
Their statement read: "Following further revelations by the Telegraph and a follow up LMA meeting with the FA this morning, the LMA remains extremely concerned about allegations made against a number of managers and individuals in the game.
"Alongside the FA, and the other principal stakeholders in the game, we want to fully investigate any and all substantive allegations of corruption, quickly and comprehensively.
"Very disappointingly, this process is being delayed as the Telegraph is yet to provide to the FA, as requested, full and complete unconditional disclosure of all the information it has.
"We urge the Telegraph to provide full disclosure of all its information relating to the allegations, including all recordings, transcripts and full details of how the information was obtained, to the FA, immediately.
"This information should not be provided selectively, but unedited and unconditionally, in order that a fully comprehensive investigation can be expedited."