Two Manchester United fans' groups are meeting former Football League chairman Keith Harris to discuss how to ward off any takeover bid by Malcolm Glazer.
The move by the Independent Manchester United Supporters Association and Shareholders United comes after the US tycoon increased his stake in United.
Glazer now has a 28.1% share of the club but any takeover move is not thought to be imminent.
IMUSA and SU have agreed to meet Harris to identify any areas of common ground.
SU's Oliver Houston said: "Our focus is deterring Glazer from making a bid."
He added: "Our central aim is to build the collective shareholding of fans through SU's share scheme and our soon-to-be-launched supporters' trust to provide the club and its fans with long-term stability and security.
"We appeal to anyone interested in working with the fans in our club's hour of need to come forward now and talk to us."