Carlisle, chairman of the PFA, revealed he has already had several meetings with Reading striker Roberts, who, along with Ferdinand, refused to wear a Kick It Out T-shirt at last weekend's English Premier League games.
However, the nature of the proposals surrounding the potential breakaway group, which could sever links with the PFA, are still unknown by the union, and Carlisle has called for the key players to meet and discuss their objectives and issues which have caused the movement to gather momentum.
"I've had a number of conversations with Jason over the past few months. The most recent of them was on Sunday and they will continue," Clarke said.
"Jason explained one or two things to me but I don't know what the full intentions or the requests are of this breakaway group.
"Until we get everyone in and fully ascertain what they want and the direction they want to go in I can't really comment much further.
"The threat is very real because the proposal is there and the discussions have been had so it's obviously something that has been mooted within the industry.
"We have been having meetings with Jason and we have desperately been trying to get Rio into the meetings and that will continue.
"We will have those discussions with them at the time. We need to know exactly what it is they are wanting. Whether this is a movement that is in full flow and whether they think it is going to happen irrespectively, or whether it is something where they are trying to instigate change within the organisations that are currently in place.
"These are things that we have to hear, assess and weigh up."
Clarke is concerned the potential formation of a separate players' union could derail current efforts to drive racism out of football.
Manchester United defender Ferdinand, whose brother Anton was the subject of racist abuse from the Chelsea captain
Carlisle backed Ferdinand's right to free speech after his protest but is cautious about the benefits a breakaway group would bring in the fight against racism.
"It has the potential to be divisive as when you establish a black players union it would instantly define 'us and them' and that's something we really need to work against," Carlisle said.
"We don't need to separate the players when the whole focus and goal of anti-racism is to campaign for unity so that is something we will be talking about, definitely."
However, the PFA chairman believes the
Carlisle said: "I feel the FA need to respond by addressing all of the issues that have caused all of the discontent over the last 12 to 18 months and that's the reporting mechanisms, the investigation process and the sanctions levied for racial abuse offences.
"A four-game ban (for
"The message that was sent out was that racial abuse can be mitigated against and that message is diluted in the next case.
"I think eight games is a minimum entry level. The FA did punish
Taylor said: "If any sporting union or profession has done as much, or worked as hard to eradicate racism, I'd be pleased to know of it.
"Experience has taught me that racism has to be dealt with as a group, a group of footballers or society as a whole."
England is looking for a new Under-21s manager after Stuart Pearce was informed he will not be kept on.