Roberts, the 29-year-old Blackburn Rovers' striker, played for Jewell at Wigan.
Whelan, a 23-year-old midfielder, is currently with Sheffield Wednesday.
"There is always going to be speculation as we approach the January window, not just surrounding this club but all clubs," said Jewell.
"We have already been linked with a couple of players. I'm not saying they aren't good players but I've certainly not spoken to anyone about them.
"I will not comment on speculation."