The highly rated 18 year old appeared in over 20 games for Fulham last season and scored in the Europa League against Odense.
City have signed him on an emergency loan to cover the injuries to Criag Bellamy and Tommy Smith.
If the paperwork is completed in time Frei could feature against Burnley tomorrow. He has recovered from an injury that has seen him miss out on Fulham's season so far.
His loan spell is due to end after the game with Sheffield Wednesday on December 2nd.
"We felt that with the two boys out injured it leaves us light on numbers," said Malky Mackay. "Kerim can play wide or in behind a striker. He is young, but played in 16 Premier League matches for Fulham last season.
"They think highly of him. He is technically comfortable on the ball. He is an attack minded player."
Frei was boprn in Austria, raised in Switzerland but plays for the Turkish national side.
"My father was born in Bayrampasa, Istanbul. He migrated to Switzerland due to economic hardships, but would always take me to Istanbul for holidays and festivals. Bayrampasa has always had a special place in my heart.
"I am an ambitious person and aim to do well in England, I can play in any midfield position and on the wings as I can use both feet well.
"My father who is Turkish and my mother, who is Moroccan, advised me to play for the Turkish national team despite having represented Switzerland at under-19 level."
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