Rabiu Ibrahim has been granted a work permit, allowing Celtic to complete the signing of the Nigerian midfielder, the Glasgow club has announced.
The 20-year-old agreed a three-and-a-half year contract last week after a successful trial.
Ibrahim, a Nigeria Under-23 international, recently negotiated the termination of his contract with Dutch outfit PSV Eindhoven.
He first attracted Celtic's attention when with Sporting Lisbon.
And he claims that it has long been an ambition to join the Glasgow club.
"I feel very happy and excited to be joining Celtic," Ibrahim told the club website. "I have wanted to join Celtic for a long time to develop myself.
"They were interested in me in 2010 when I was with Sporting Lisbon.
"I don't know why that never happened, but that was then and I'm happy now that I'm here at Celtic.
"The atmosphere here is great and the people are great.
"They are always nice to me and encouraging me, so I already feel at home.
"The players have made me feel welcome and happy. It's just like a big family here. They carry everybody along and I'm happy with that.
"I'm happy that I'm here and strongly believe that I will get the opportunity to prove myself and improve my game."