The Serbian - who featured at this summer's World Cup - played 14 times for the Bluebirds during the second-half of last season as they secured promotion to the Premier League.
“Grujic looks like he will stay put," Warnock said. “I think he would be better off here but it is a contract issue, I understand his point of view.
“Liverpool have four competitions before Christmas and he can play in those without being named in the 25-man squad.
“I have missed out on a couple of targets waiting for him, it is disappointing as everything was agreed with Liverpool. But sometimes fate intervenes."