Bullard has been tipped to leave the KC Stadium this summer after spending the second half of last season on loan at Ipswich Town.
Ipswich boss Paul Jewell has suggested a renewed deal for the 32-year-old could be out of Town's reach and Bullard has been linked with a move to Premier League new boys QPR.
The Tigers' head of football operations Adam Pearson acknowledged QPR have been in touch, but have yet to follow up with a bid.
Pearson confirmed Bullard has joined the rest of the Hull squad for the trip to Slovenia and he is currently part of manager Nigel Pearson's plans for the coming campaign.
"The situation with Jimmy is that he's gone to Slovenia as part of the first-team squad and I genuinely can't see that changing," Adam Pearson told the Hull Daily Mail.
"We've had a bit of interest from QPR, as has been widely reported, but that hasn't come to anything.
"Jimmy is fit, he's come back in good shape and he's part of the first-team plans for sure.
"He looks to have a smile on his face and let's hope he can play a part for us."