The federal government's failure to ratify the China-Australia extradition treaty has sparked open warfare between supporters of Prime Minister Malcolm Turnbull and Tony Abbott, with the ex-prime minister unloading on his "cowardly" colleagues for briefing against him and botching the treaty deal.

Foreign Minister Julie Bishop delivered a slap to Liberal MPs, who on Monday threatened to revolt and cross the floor rather than back the treaty, which was signed by the Howard government in 2007 but never ratified.

She accused those dozen MPs - including Eric Abetz, Kevin Andrews, Andrew Hastie, Trent Zimmerman, James Paterson, Dean Smith and Tim Wilson - of effectively not trusting Australia's own legal and political system to block extradition to China when a person set to be sent there faced, for example, torture or the death penalty.

Mr Abbott on Friday intervened in the debate over the treaty, which has been shelved, much to the embarrassment of the Turnbull government, providing News Corp details of a briefing note from his former Department of Prime Minister and Cabinet, dated December 19, 2014.