Curtis Weston will not be offered a new contract by recently appointed Gillingham manager Martin Allen.
The midfielder was released by the Gills in May but returned to the club for pre-season training.
Allen told BBC Radio Kent: "I had a chat with him on Monday and I'm not ready to make a decision on him. I told him he could leave."
The 25-year-old scored 19 goals in 167 appearances during his four-year spell at Priestfield.
Allen added: "He asked me for a decision and I told him I couldn't make one. He's left the club now.
"I said 'good luck'. He said 'thanks'."