He becomes Celtic's first signing since Brendan Rodgers returned as manager.

Rodgers has "looked at him closely" and expects Holm to "make a big impact at the club".

Holm has started all 10 games this season for the side sitting 13th in the Eliteserien, one place above the relegation zone, having helped them finish sixth last year.

The playmaker has represented his country up until under-20 level.

"He is a player who has been in the club's scouting and recruitment system for some time," Rodgers told Celtic's website.

"I have spent time already with Odin - he is an ambitious, exciting young player and I know he is delighted to be joining us."

Holm applied for permission in 2017 to add Thiago as a middle name because he views Liverpool and Spain midfielder Thiago Alcantara as a role model.