Both players have broken into the Pompey first team this season with a number of scouts in attendance at Fratton Park in recent months to track their progress.
Although Whittingham is hopeful the League One strugglers will be able to keep hold of the pair, the caretaker boss admits they would have to seriously consider a strong bid.
He told The News: "If someone came in with £3m we are not going to be stupid and say no.
"Obviously there is interest in them because they are playing in the first team. I am not saying we are looking to sell, we are not, but that always might happen.
"If they do go it won't be because we want them to go, it will be because finances dictate the offer is the best thing for the football club."