Jack was named in the squad for games against Austria, on Thursday, Israel and the Faroe Islands but he has not played for a month because of a calf problem.
When asked about Jack after Monday's training session, assistant coach Steven Reid said: "No update at the moment, there's still some discussions to be had."
Reid added: "We had a small group to train with, got most of the players out on the pitch for a really light session. A few players did a bit extra.
"But all fit and well so far and hopefully it stays that way."
Rangers boss Steven Gerrard has spoken to Scotland manager Steve Clark about the fitness of his midfielder.
"We've been in touch over Ryan (Jack) and a few other players but I'm not going to divulge what gets said in the conversation,” he said.