Wickham, 17, is the Tractor Boys' youngest-ever player and a target for the Reds, who are ready to swoop in January, as well as Premier League rivals Arsenal and Tottenham.
The £10million-rated star's goals helped England to win the European Under 17 Championship last summer and he recently stepped up for his Under 21 debut.
Big bucks: Wickham (right) will not be allowed to leave Ipswich on the cheap
A series of injuries have blighted his progress this season and he is still waiting to score his first goal of the campaign.
Keane said: 'There aren't many Connor Wickhams around. You've got to be careful not to get blas?bout Connor and say "we'll take £7m or £8m for him".
'I have a certain figure in my head that we'd have to consider. I think Connor and his agent would have that as well.
'The big teams wouldn't be buying him for what he's doing now. They're going to buy him for what he can do in four or five years' time - his potential.
'Whether that's Tottenham or Liverpool or whoever, but United had to buy Rooney for £28m when he was 18.
'Can Connor be as good as him? I think he has the potential, but that's up to the club. I don't think the club has had any concrete offers yet.'
EXCLUSIVE: Kop shop! Liverpool line up £10m deal for teenage ace WickhamRonaldinho to Liverpool? Anfield midfielder Lucas keeping fingers crossed rumours are trueAmerican writer hits out at Liverpool fans in mourning for Hillsborough 'riot'Halfway there! Reina challenges Reds to show they can be 90-minute menLIVERPOOL FC