The Gunners are currently seven points behind Manchester United with a game in hand over Sir Alex Ferguson's men.
And with the Old Trafford outfit set to travel to London in May, the Frenchman believes that is no longer any room for error in their quest to win the Premier League.
The former Monaco boss also hit back at suggestions that his team may already be out of the title race, telling reporters: "At the end of the season we have to think we have given absolutely everything to achieve it and to do it.
"At the moment we are still in it [the title race]. Not many people give us a big chance - but no matter how big [or small] the chance is, we have to fight for it."
Wenger added: "If we do not beat Liverpool and Tottenham [on Wednesday], the season won't be over, but the title will be over for sure.
"It [the title] is not 100 per cent even if we win our games, but we know what we have to do, which makes Sunday vital of course."