Two Raheem Sterling goals and Luis Suarez's 30th league strike of the season helped Liverpool to their 11th consecutive Premier League victory and ensured them of a place in Europe's elite club competition next season.
They moved to 80 points, five ahead of Chelsea who suffered a shock 2-1 defeat by bottom club Sunderland on Saturday. Third-placed Manchester City, on 71 points and with two matches in hand, play West Bromwich Albion on Monday.
Arsenal, for whom Lukas Podolski scored twice after Aaron Ramsey's opener, moved to 70 points, one clear of fifth-placed Everton, who beat United thanks to first-half goals by Leighton Baines and Kevin Mirallas.
Liverpool have not won the title since 1990, two years before the Premier League began, and they can move to the brink of ending that drought when they meet Chelsea at Anfield next Sunday.
(Editing by Ed Osmond)
