Chelsea are chasing the Nigeria international and have had one offer already turned down.
Whelan is keen to keep the winger, signed from Crystal Palace for £2.5million in January 2010, at the DW Stadium for a while longer as he believes the player is developing well under manager Roberto Martinez.
"I personally have told Victor he requires another 12 months minimum under Roberto's guidance before he thinks about moving to a top club," the chairman said.
"He has come on so much in the last two years - and that is purely down to Roberto's help.
"I told him when he signed for Wigan that we'd let him go when the time was right and a big club came in for him.
"In my opinion he's not quite ready for that yet, but another year working with Roberto and he might be."