The 18-year-old has been heavily linked with a move to Chelsea and Manchester City this summer after impressing at Lisbon over the past season.
The youngster scored five goals for Portugal at the Under-20 World Cup in recent weeks, but Bruma looks set to quit Sporting after failing to agree a new deal.
“Now Bruma heads totally out of Sporting. If the case goes through the courts, no problem,” said Bruma’s lawyer Bebiano Gomes.
Bruma backed up his lawyer’s claims and admitted he was disappointed that he was unable to agree a deal with current employers.
“I deeply regret the outcome of this matter. I did everything to stay at Sporting and I made it clear to my representatives to try to reach an agreement. But after all this time, Sporting did little for me to renew,” Bruma told A Bola.
“I want to avoid any sort of controversy with Sporting and especially with the fans. I am a professional and I will continue my career.”
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