The 24-year-old former Millwall and MK Dons winger was offered a deal to stay at McDiarmid Park but indicated he wished to head back down south.
"Fil expressed an interest in finding a club in England and I believe he may be looking to get back to the London area," manager Derek McInnes told the club's official website
"I've not heard from his agent so, as far as I am concerned, we move on and search for a replacement."
Morais joined Saints last summer after spells at Hibernian and Inverness.
Source: PA
Source: PA