Phillips, a midfielder, only returned from two months on the sidelines following shoulder surgery as a substitute in the midweek League Cup win over Chelsea.
Right-back Walker has not played since suffering an abdominal injury, which later needed surgery, in the derby against Manchester United on October 2nd.
City manager Guardiola, however, said Friday: "You saw Kalvin in the last game, he is ready. Kyle - not yet.
"It is a decision from Gareth Southgate and I support, 100 per cent, his decisions. I am not involved. After Saturday the players belong to the national teams, they don't belong to us. I am not worried at all."
Guardiola, speaking at a pre-match press conference, was coy over whether Erling Haaland (22) would return to the starting 11 for the Premier League champions' clash against Brentford on Saturday.
The Norwegian star has featured in just one of City's last four games, coming off the bench to score a late winner against Fulham last weekend.
"We will see," said Guardiola, whose side are just two points behind Premier League leaders Arsenal. "We have training this (Friday) afternoon. He is a little bit better."
Guardiola, out of contract at the end of the season, refused to say if he would use the upcoming World Cup break to discuss his future with the club.
"I've said many times, I don't talk about that," he said. "Everything is under control. It is perfect. A decision will be made, together with the club, the moment it has to be made."
