The Israeli is thought to only require a work permit to conclude the deal after agreeing terms and undergoing a medical. According to his representative, Dudu Dahan, Gershon will return to Belgium to conclude the necessary paperwork before joining Celtic at their training camp in Marbella.
Should his short-term move prove successful, there is the option of Celtic buying the player from Standard Liege in the summer, with Gershon and Celtic having already signed off on a three-year contract.
"I'm very happy to sign for this fantastic club and I'm ready for the great challenge," Gershon said on his agent's Facebook page. Dahan added: "Everything was closed to the satisfaction of all parties. The only issue that remains now is getting a work permit. That should be settled next week."
Meanwhile, Maor Melikson, a former Celtic signing target also represented by Dahan, has been told he can leave Wisla Krakow. The Parkhead side had a £1.25m bid for the Israeli midfielder turned down on summer transfer window deadline day but the player has now been told he can leave if his Polish club receives a suitable offer.
"He has put in a transfer request, which was accepted," Jacek Bednarz, vice-president of Wisla, said.
Juan Agudelo, the American international who trained with Celtic last month, is now on trial at West Ham United.
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