Director and major shareholder Paul Barry has claimed that there are "deep divisions within the club at staff and board level" at Cambridge United.
His comments follow the appointment of Brian Attmore as acting chairman.
Attmore, a fans' elected director, replaces Terry Baker, who resigned as chairman at Monday's board meeting after just four months in the role.
"The current board agree they cannot work together on a long term basis," Barry told the club's website.
"A unified management and board needs to be put into place as soon as reasonably possible, along with fresh investment that will move the club forward for the next three years.
"The club needs to face reality and match its off-field expenses with that of a Conference club, and maximise its use of the stadium on non-matchdays, which it has failed to do."