RONNY DEILA today told Virgil van Dijk that if he helps Celtic into the group stages of the Champions League he will attract the attention of one of Europe's elite clubs.

The 21-year-old defender has been linked with a move to the Barclays Premier League this summer, but Deila is not for selling.

The Celtic manager has already told the player that another season at Celtic can make him a more complete performer - and pave the way for a move.

Celtic's resolve may well be tested with a significant offer for the player, but Deila has insisted both he and chief executive Peter Lawwell are of the mind that it is far more lucrative for the club to feature in the Champions League than it is to cash in on Van Dijk.

Asked if his opinion would change if there was an offer of £7-£8million on the table for the defender, Deila said: "I would say no. Because we would get that at Christmas, maybe more.

"It's much more money from being in the Champions League and we'd lose one of our best players. Peter would rather go to the Champions League than sell Virgil."

The danger, of course, is that Celtic don't make it through the qualifiers and into the lucrative group stages.

He added: "We have to take that decision after - we can't do it before. 'Oh we don't come to the Champions League, so we sell Virgil van Dijk' - of course we won't do that.

"Virgil needs a very good campaign with Champions League football, and if he does well there, it's easy to get to the big clubs. I've said all the time that Virgil is a high-class football player and he should go to the best clubs in Europe, not small clubs in England.

"We have to think of the best interests for the club as well and also for him. It's no problem for him to go to a Champions League club."

Deila has spoken with Van Dijk about his future and the key will be with the player. Should the defender insist he believes he has reached his ceiling at Celtic, then it would become very difficult for the club to stand in his way.

However, if he takes on board the advice of Deila, then he may be persuaded that another season in Glasgow is to his benefit.

"In my opinion he has the biggest potential in a defender I have ever seen," enthused Deila."That's not right for a smaller club fighting for relegation.

"He is a good player with the ball, on the ball. He is a good personality as well and his biggest tests have still to come.

"He will be at the top level in the Champions League if he does the right things. I have told him that.

"He hasn't experienced everything. If he plays well in the Champions League then the biggest clubs will come for him.

"That's where he should be - not playing for smaller clubs in England. I am talking about the big clubs in Europe.

"I think he has more to improve. He was a little bit unlucky in Milan, I think he was unlucky with the red card.

But I think he still can learn a lot here through the Champions League and get more experience and show what a class player he is."