The Red Devils currently hold a seven-point lead at the top of the Premier League table, although that will be cut to four points before they meet Tottenham Hotspur tomorrow afternoon if Manchester City defeat Fulham at the Etihad Stadium later today.
However, England international Welbeck has insisted that United should only be focused on their own results.
"Our main focus is ourselves and we're not looking at anybody else," Welbeck told the club's official website.
"Getting three points is the main thing and we're not looking for any other results. Obviously, City could shorten the gap and it is key that we maintain our seven-point lead.
"Every game we play in the league is important and the main thing is to go out and get the three points. We can't watch other teams and see how they are doing. We have to look after ourselves."
Welbeck has scored one goal so far this season.