Both games will be held at an empty Wembley over the weekend of July 18-19.
City booked their clash with the Gunners after a Kevin De Bruyne penalty and Raheem Sterling goal saw off Newcastle on Sunday evening.
Newcastle great Alan Shearer conducted the draw during half-time in the last-eight clash between Newcastle and City at St James’ Park.
It was the first Covid-secure FA Cup draw, with just Shearer – watched by Gary Lineker – pairing up the teams, instead of the usual two guests.
City faced Arsenal in a Wembley semi-final three years ago, where Arsene Wenger’s side managed to prevail over Pep Guardiola before going on to lift the cup.
But City have been rampant against Arsenal in recent years, and beat Mikel Arteta’s side 3-0 when they faced each other 10 days ago in the first game back from the coronavirus hiatus.
The clash between United and Chelsea is a repeat of the FA Cup final from two years ago, where Eden Hazard’s penalty gave the Blues victory. –Mailonline