Dumped prime minister Malcolm Turnbull is reportedly set to quit federal parliament this week and spark a by-election in his seat on October 6.
Nine Network and the ABC report Mr Turnbull will quit parliament this week, after he promised he wouldn't stay on the back bench.
The move will leave the coalition one seat down for two sitting weeks, leaving new Prime Minister Scott Morrison in a precarious position with no majority in parliament.
Just days after Tony Abbott helped orchestrate Mr Turnbull's demise, he is now campaigning for his sister to replace him in his plum Sydney electorate.
Mr Turnbull is yet to announce his resignation from the harbourside seat but told reporters last week it won't be long.
Christine Forster on Monday confirmed she intends to run for Liberal pre-selection in Wentworth after being encouraged by several people within the party to replace the ousted prime minister.
Businessman and former Australian ambassador to Israel Dave Sharma is said to be the frontrunner to replace Mr Turnbull as the Liberal candidate.
NSW MP Alex Greenwich and GP Kerryn Phelps are also both considering running as independents.
Waverley Deputy Mayor Dominic Wy Kanak has been announced as the Greens candidate for the seat.
Tamarama Surf Lifesaving Club president and local businessman Tim Murray will run as Labor's candidate.
