The 22-year old Swedish striker is on a season-long loan with the Hoops from Manchester City where he is unlikely to force his way into the first team anytime soon.
Guidetti has recently bene linked with a possible winter move to Southampton but Deila is confident he will at least keep the former PSV Eindhoven ace at Celtic Park until the end of the current campaign.
"We've been speaking with John for a long time but he's decided now he wants to wait to see what his options are until March or April, maybe longer, so there won't be any final decision this month," said Deila.
"But we know we have him until the end of the season."
Since arriving in Glasgow, Guidetti has scored 11 goals in 18 appearances in all competitions including six in the Scottish Premiership.
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