West Ham bid for Benni McCarthy
Blackburn said the experienced striker had failed to turn up for their last two training sessions.
"We are very disappointed with Benni's non-appearance for training and will deal with it separately should he remain here after the transfer window has closed," manager Sam Allardyce told the club's website.
"We have said all along we will listen to offers but only agree to sell if both the commercial and football reasons satisfy Blackburn Rovers. That situation remains unchanged."
McCarthy is expected to be in host nation South Africa's squad at the World Cup in June.
They have been drawn in Group A with Mexico, Uruguay and France.