The 22-year old Swedish striker, who is on a season-long loan from Manchester City, is likely to leave his parent club in the summer.
Reports suggest Italian side Inter Milan are showing considerable interest in Guidetti, who has 13 goals in 24 outings for the Hoops, but Deila believes he should continue to develop in the Scottish Premiership.
"That's new to me, but I think it will not be the last club we'll hear about," said Deila.
"He should stay here at Celtic. He's enjoying his stay and is going to get better."
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