Inter had also been scheduled to play Portsmouth, Crystal Palace and Norwich, but the terrorist atrocities in London led to a rethink.
City will now travel to League Two outfit Boston United on Monday night (7.30).
City will come face-to-face with former striker Julian Joachim at York Street.
City boss Craig Levein remains confident Plymouth left-back Peter Gilbert will be joining his squad in time for the start of the new season at Sheffield United on August 6.
Plymouth say the initial offer has been rejected, but Levein is upbeat the situation will be resolved next week.
Levein will then turn his attentions to boosting his strikeforce and hasn't ruled out the possibility of securing a loan signing.
His striking options at the moment are David Connolly, Dion Dublin and Mark De Vries with Lee Morris still injured and Tommy Wright out of favour.