KRISTOFFER Ajer can increase his chances of representing Norway in the seasons to come by committing his long-term future to Celtic, according to legendary international manager Lars Lagerback.

Lagerback, the former Sweden, Nigeria and Iceland head coach, has called Ajer into the Norway squad for the first time for their friendlies against Australia in Oslo and Albania in Albasan next week.

The 69-year-old has been delighted to see the promising 6ft 5in player force his way into the first team in Glasgow and become a regular starter during the 2017/18 campaign.

In particular, he has been pleased to see the 19-year-old feature in Champions League qualifiers against Rosenborg and Astana and the Europa League last 16 games against Zenit St Petersburg this term.

The man who led his native Sweden to five consecutive tournament finals – three European Championships and two World Cups - during the eight years that he spent in charge of his homeland believes being involved in continental competition will be hugely important for his development.

Despite the fact that Norway have failed to qualify for a major finals since Euro 2000, Lagerback currently has defenders who play for Hoffenheim in Germany, Palermo in Italy and AZ Alkmaar in the Netherlands.

He feels that Ajer remaining in Glasgow and being involved in European competition every season will improve his international prospects significantly and is keen to see him put pen to paper on the extension he has been offered.

Ajer, who was signed from Tippeligaen club IK Start by former Celtic manager Ronny Deila in a £650,000 deal two years ago, is currently under contract at Parkhead until the summer of 2020.

However, Brendan Rodgers is keen to keep the versatile player, who can play at centre half, right back or in midfield, and the Scottish champions have offered him a lucrative new deal on improved terms.

“The higher up a player can play the better it is for me when it comes to picking a player to be involved in international football,” he said. “Playing in the Champions League and in the Europa League is giving him experience that you can’t buy. You have to gain that experience yourself and he is doing that playing for Celtic.”

Lagerback – who led Iceland to Euro 2016, the first major finals in their history, and oversaw a famous last 16 defeat of England, before taking over at Norway last year – knows a decent player when he sees one.

He worked with Zlatan Ibrahimovic, who he handed his international debut to when he was the same age as Ajer, Henrik Larsson and Freddy Ljungberg among many others during the time that he spent in charge of Sweden.

He declined to speculate on how far Ajer can go in the game before he had even won his first cap for his country, but admitted that his new recruit’s showings at club level augur well for the future at international level.

“We have picked Kristoffer for the upcoming friendlies,” he said. “That tells you we are very much aware of him and what he has done. What he has done since he started to play regularly for Celtic before Christmas has been impressive. He has shown that he’s a very promising player.

“It is very difficult to compare him to the players we have who have qualified for the squad at the moment until we see him in training. He’s a very young player. What I am hoping of course is that he will develop and keep on getting better and better in the future both with Celtic and in international games with Norway.

“We want to have him in the squad now to have a look at him. We will see how much that he plays. But I think he has done very well with Celtic. Hopefully he will be able to transfer that to international football with Norway.”

Ajer benefitted greatly from spending the second half of last season at Kilmarnock on loan; he switched from being a central midfield player to a centre half during the 17 games that he played for the Rugby Park club and has since stated that he sees his future in that specialised position.

But the teenager played for Celtic at right back against Rangers at Ibrox on Sunday and helped his club record a 3-2 triumph which sent them nine points clear of their city rivals at the top of the Ladbrokes Premiership table with a game in hand and has as good as guaranteed they will win a seventh consecutive title.

Lagerback will reserve judgement on where the player, who became the youngest skipper in Tipppeligaen history when he captained Lillestrom at the age of 16, should play in future for Norway until he has worked with him personally.

“It is difficult to say where his best position is until we have seen him play for us,” he said.

“Since I have started with Norway I have only seen him as a centre back, as a defender. I think he is doing really well there. He can defend, but he can certainly pass the ball very well. That is not a bad quality to have as a central defender.

“But the most important thing for him to be able to do in this role is to defend and he has shown that he can do that really well with Celtic. That is why we have picked him to play for the national team.”