Arsenal appeared to come close to entertaining bids for Walcott when negotiations over a new deal - to replace the one that expires next summer - stalled during the last transfer window.
And despite having previously set a deadline of the end of 2012 for an agreement to be reached, Wenger insisted after Saturday's 5-2 north London derby thrashing of Tottenham that Walcott was going nowhere in January.
Asked if the winger would be sold if the impasse continued into 2013, Wenger said simply: "No."
Pressed on whether Walcott would see out the season at Arsenal come what may, he replied: "Yes."
Wenger's revelation opened up the possibility of Walcott signing a pre-contract agreement with a rival club, Liverpool and Manchester City having both been linked him.
The Arsenal boss remained confident of a deal being reached before then.
Asked if talks were closer to bearing fruit, he joked: "If I listen to you then every day it gets more expensive. We continue in a positive way. I told you many times we have until the end of December to sort this out."
Jack Wilshere, Walcott's team-mate for both club and country, does not want to see another big name player quit the Emirates Stadium.
"He is an English lad and great to have around the dressing room," the midfielder said. "But that is up to him, the boss and the board. They are going to do whatever they are going to do. I hope he signs.
"We all know what Theo brings to the team. He has got pace, he can go behind and his movement and timing of the runs is probably the best around.
"He can play anywhere - up front, right, left, central. He wants to play down the middle, so I think he will get his chance - he will just have to be patient."
Walcott himself claimed he was prepared to do that after reiterating he saw his long-term future up front.
It is an assurance of more playing time as a striker - as much as a bigger salary - that the player is said to be seeking.
And despite being made to wait until the 86th minute on Saturday to show what he could do in the position, he still managed to rack up his fifth goal in as many games.
Wenger said: "It is always good when you can play everywhere."
He pointed out Olivier Giroud could hold the ball up in a way Walcott "will not be capable to do" but added: "He is a different type of player but he can play up front, and he can play up front with Giroud as well.
"I think he has found a good mixture and good positional play on the wing."