FAN on the board Peter Garston has called on fellow Millwall supporters to sign a petition against a council decision to sell land around The Den to a developer.
Garston, who has represented Lions fans in boardroom discussions since April 2006, wants Lewisham council to reconsider their deal with Renewal.
Contracts have been exchanged on the sale of three pieces of land adjoining the stadium, which are currently leased to the club and their community scheme.
Millwall claim that their own proposals for the area were ignored by the council, and that they were not given the chance to bid for the land before the deal with Renewal was agreed.
Garston said: "We urge Lewisham council to stop this sale and get back round the table to consider Millwall's plans."
Over a 1,000 fans have signed the petition since it was launched this morning.
"We need as many signatures as we can possibly get to turn the council's head," Garston added. "If everyone can get behind it, we're in with a chance."