Porto, who secured the trophy last year under the guidance of now Chelsea boss Andre Villas-Boas,will  host City in the first leg before a return fixture at the Etihad Stadium, while United will play in the Amsterdam ArenA first.

In the draw for the last 16, United discovered they will face one of Lokomotiv Moscow or Athletico Bilbao if they get through. City will take on either Legia or Sporting if they see off Porto and a victory over Valencia would see Stoke play either Trabzonspor or PSV Eindhoven.

Stoke manager Tony Pulis said: "It's a great draw for us. Valencia are one of the top teams in Europe with great traditions in the European competitions.

"Tony was desperately hoping that they should get a draw against a big club where our supporters wouldn't have to travel too far because they have been looking forward to an opportunity such as this one where they can go to the away leg.