RONNY DEILA has claimed Celtic are "in control" of Anthony Stokes's future and said he was unconcerned about speculation that Cardiff City want to sign him in January.

The Republic of Ireland striker turned up just in time to make Celtic's flight to Croatia yesterday - he arrived only a few minutes before the gate closed for the 11am flight from Glasgow Airport - but, while Deila claimed Stokes' fitness could be better, he said there was no desire for the player and club to part company.

Stokes, 26, has been at Celtic Park since 2010 and signed a new three-year deal under the previous manager Neil Lennon in October 2013. He has played regularly since Deila took over this season, most recently as an attacking left-sided midfielder.

Earlier this week, Cardiff City were reported to be prepared to pay £1.5m to take him to the Sky Bet Championship in January.

Deila said Stokes should work to improve his physique and his running, but that he sees him as a valuable part of his squad. "I think Anthony is happy and I've been talking to him a lot. I'm not afraid. He's under contract and I'm in control of the situation.

"We want to build the best team we can for Celtic and I think January transfer window will see us strengthen rather than weaken. We will see what possibilities there are. We always look at the players and think of what is the best for the future for the club and the right way to go.

"Nobody is for sale ... but then everyone is for sale as well! If someone comes in with money where we can't say 'no', then of course we must think about it. But they are all very expensive. I haven't heard anything from any [other] clubs about any of our players. It is just speculation."

Stokes has scored seven times in 24 appearances for Celtic this season including the winner against Motherwell on Saturday. Deila has moved him from his preferred role as a central striker and tended to play him on the left of a three behind John Guidetti or Stefan Scepovic. The 26-year-old had not completed his development as a player, as far as Deila was concerned.

"He has been good but he is not there yet. He needs to improve physically so he can run even more and he can get even sharper. He is an important player because he is scoring goals and he is a very intelligent player. He knows how to play and he can link up well with the other players as well. He needs to get his fitness up for the highest level. His attitude is very good."

Deila caused a stir earlier this season when he said the Celtic players' diet and fitness had to improve, and it was a point he repeated yesterday in relation to Stokes and others.

"Every player have areas where they can improve. We've improved a lot but some of the players aren't as fit as they can be at international level. We're not talking about domestic games where it's easier to win but we have to have Champions League standards. In Europe [other clubs] have developed a lot in the way they train and in the north of Europe they're not in the same level because of the weather and things like that. We must look at every aspect of what we're doing and try to improve and get as close as possible to these teams."