"I understand the comradeship," he said. "I understand the sense of satisfaction and pride you get from the service and I just want to say there are times that I envy you that because there is something unambiguously good about the work that you do for our community."
Abbott paid Key a big compliment yesterday after their talks, congratulating him for his leadership of a successful centre-right Government.
He also commended him on committing New Zealand to take part in a joint New Zealand-Australia troop training mission to help Iraq in the fight against Isis.
It was a "right and proper" decision.
"As far as I am concerned, good on John Key for being there to shoulder a reasonable share of responsibility for this particular battle because the death cult is reaching out to the world.
"Australia is proud to be part of an international coalition working to disrupt and degrade and ultimately to destroy this death cult."
He is expected to make a formal announcement next week after he has consulted his party caucus. Having had his leadership challenged partly on grounds of a non-consultative style, he is taking more time over decisions.
Abbott and his wife Margie left last night to return to fight for his political life and try to prevent another caucus vote on his leadership. Audrey Young and AAP