Phillips returned from World Cup duty with England "overweight" and not ready to feature against Liverpool, according to City manager Pep Guardiola.

The midfielder has endured a frustrating season hampered by injury issues after moving to the Etihad Stadium from boyhood club Leeds United.

Phillips was still selected by Gareth Southgate for Qatar 2022 but played just 40 minutes across the tournament before England suffered quarter-final heartbreak against France.

The 27-year-old, who has been restricted to just one substitute appearance in the Premier League for City, missed the Carabao Cup fourth-round win over the Reds.

While England team-mates Jack Grealish, John Stones and Phil Foden all featured in the first game after the World Cup, Guardiola suggested Phillips' fitness was far below the standards expected.

"He's not injured. He arrived overweight. I don't know [why]," Guardiola said when asked about Phillips' omission.

"He didn't arrive in the condition to do training sessions and to play."

Guardiola is not giving up on Phillips yet, though, adding: "When he will be ready he will play, because we need him, we need him a lot."

As for Guardiola's disappointment with him, he said: "It's a private conversation with Kalvin."

Guardiola confirmed Ruben Dias joined Phillips on the sidelines after sustaining a hamstring injury in Portugal's World Cup quarter-final defeat to Morocco.

City visit Phillips' former side Leeds on Deember 29 (AEDT) as second-placed City aims to cut Arsenal's five-point lead at the top.