FREMANTLE has warned rival AFL clubs that Robert Warnock will not come cheap as the trade war hots up for the talented ruckman.

Warnock advised Fremantle on Wednesday that he will be returning home to Victoria, with Melbourne and Carlton in hot pursuit of the 21-year-old and Richmond also believed to be in the hunt.

But football operations manager Chris Bond fired a warning shot to potential suitors, saying Fremantle would draw a "line in the sand" with how they negotiated with other clubs.

The task of getting a good deal for Warnock will be a delicate balancing act for Fremantle, who run the risk of losing the uncontracted Victorian for nothing via the pre-season draft should a trade not be agreed upon.

Melbourne, who won just three games this season, have first pick in the pre-season draft.

"There needs to be a line in the sand ... what happens is really important for the Fremantle Football Club," Bond told radio 6PR.

"We will still decide what is best for the football club, and I know there is a threat of losing Robbie for nothing.

"I am very conscious of the fact that we will make a stand, and we believed Robbie was a very important part of our future.

"We have discussed whether we feel everything that could have been done was to keep Robbie, and we have absolutely no doubt (it was).

"The club has gone beyond the call with everything they could for Robbie, and I think he realises that."

Bond said Fremantle was open to the prospect of a complex trade involving multiple clubs.

"To think you are just going to be dealing with one club when you are dealing with someone in demand like Robbie is probably naive," Bond said.

Warnock is yet to make his intentions clear about which club he would like to be traded to.

His brother, Matthew, plays for Melbourne, while his former coach Chris Connolly is now football operations manager at the Demons.

But the prospect of linking up with emerging ruckman Matthew Kreuzer at Carlton to spoon feed the likes of Chris Judd, Nick Stevens, Bryce Gibbs and Marc Murphy is also a tantalising prospect for Warnock.

Carlton football operations manager Steven Icke will hold an urgent meeting with Warnock's manager Colin Young in Perth this weekend.

Bond admitted Warnock's departure was a bitter blow for Fremantle, who are also facing a battle to re-sign talented Victorian David Mundy.

"Robbie is a hiccup in that because we wanted to build this list around Robbie," Bond said.