The Red Devils suffered a shock loss to Wigan last week but retained their gap at the top of the Premier League with a 4-0 win over Aston Villa on Sunday in response to City’s 6-1 thrashing of Norwich City the day before.
The two Manchester sides meet on April 30 in what could be the decider for the championship and De Gea admits that United is desperate to clinch the three points and take its 20th league title.
"We have the title in our hands," the keeper told reporters. "A five-point advantage is good, but the derby against City will be key. We want to win this match and to celebrate winning the title.
"The last four matches are complicated, and after the defeat to Wigan we do not want any more problems."
As a former Atletico Madrid player, De Gea has also had his say on Chelsea’s chances of beating Spanish giant Barcelona in their Champions League semifinal, admitting that it may be a case of "mission impossible" for the west London outfit.
"Chelsea have a strong team but against Barca it's nearly mission impossible," said the 21-year-old. "If Barca play at the level everyone knows they can, they will win in London and go through to the final. Fernando Torres is playing under too much pressure and that's not good for a player."
