Gareth Ward, the Parliamentary Secretary for the Illawarra, is said to be at the centre of Ms Sudmalis’ decision not to contest the next election.

“Gareth Ward should hang his head in shame today for the role he has played in ensuring another female Liberal MP is quitting Parliament,” Mr Park said.

Read more: Gilmore MP Ann Sudmalis quits over branch stacking, undermining

“It took guts for Ann Sudmalis to expose his actions.

“I doubt the people of Kiama would appreciate how much time he is spending undermining members of Parliament rather than co-operating with them in order to help his electorate – and doing so at the taxpayers’ expense.

“He should apologise to Ann Sudmalis and to the people of the Illawarra and the South Coast immediately for his behaviour.

Ms Sudmalis believed she was still likely to win her preselection against challenger Grant Schultz, but she said she would have been unable to work with the people stacked into her local federal electoral conference (FEC), many of whom had no campaign experience.

Mr Park, the Shadow Minister for the Illawarra, said Monday’s events showed how deeply divided the Liberals party had become.

In a statement, Mr Ward said he had “enjoyed” working with Ms Sudmalis on a number of projects to benefit the local community.

“I wish her and her family all the best for their retirement and look forward to working with her successor,” Mr Ward said.