The full back returned to action as the newly crowned Premier League champions beat Swansea City 5-0 last weekend.
"I can't decide (if the World Cup is too soon)," Guardiola told reporters ahead of Sunday's league trip to 15th-placed West Ham United.
"I don't know. After six or seven months, you need a bit of time to get your brain, knee and football skills back," the Spanish manager added.
Meanwhile, reports in the British media have said City's assistant boss and former Arsenal player Mikel Arteta could be a candidate to replace the departing Arsene Wenger at the London club.
Arteta was credited by Guardiola for his work in helping City win their first title since 2014.
"My opinion about Mikel is overwhelming. He deserves the best. We're so comfortable working with him. Part of the reason for our success this season was because Mikel is here," he said.
"I know there are a lot of names for the next position at Arsenal but I don't know what their plans are. Mikel deserves all that he wants."
Another name linked with the Arsenal job is Guardiola's former Barcelona team mate Luis Enrique who received high praise from the City boss.
"He is an excellent manager... he can train wherever he wants and Arsenal are one of the biggest clubs in the world," Guardiola said.
(Reporting by Shrivathsa Sridhar in Bengaluru; Editing by Christian Radnedge)
