It came as the state executive rejected a motion that would have used special powers to endorse sitting MPs and protect three Morrison government members - Immigration Minister Alex Hawke,Environment Minister Sussan Ley and North Sydney MP Trent Zimmerman - who are under threat from preselection challenges.
The ballot was rejected by 16 votes to three on Monday,according to the party officials,who are not authorised to speak publicly.
It was not immediately clear why Ms Buncle withdrew her nomination and she did not respond to inquiries on Monday night. However,party sources suggested she was unhappy about the failure to expedite the preselection process and therefore give her time in the field to be competitive against independent MP Zali Steggall,who holds the seat on a 7.2 per cent margin.
Ms Buncle’s withdrawalleaves defence analyst Lincoln Parker as the default Liberal candidate for Warringah. The state executive or federal party organisation can still intervene to impose a different candidate.
Earlier in the electoral cycle a number of Liberal operatives expressed interest in nominating for the formerly blue ribbon seat of Warringah including former Morrison aide Sasha Grebe,state executive member Alex Dore and Menzies Research Centre boss Tim James. None ultimately nominated;Mr James is now endorsed as the Liberal candidate at the Willoughby state byelection,while Mr Dore is being touted for the federal seat of Hughes.
Prime Minister Scott Morrison has courted two former state premiers to run in Warringah - Mike Baird and Gladys Berejiklian - but both have thus far rejected the offers.