The deal includes the Liberal party preferencing One Nation ahead of the National Party in the Legislative Council and, in return, One Nation putting Liberal above Labor in the Legislative Assembly.
Mr Seth said “preferences are a matter for the Liberal party”.
“The objective with preferences is to always maximise the Liberal Party vote,” he said.
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Liberal candidate for Maylands Amanda Madden also said preferences were “a matter for the party and do not actively involve individual candidates.”
“The Premier has stated that preferences are not an endorsement of other parties’ policies,” she said.
“Supporting that team and being an active and passionate voice for local residents are my primary concerns, and I will continue to focus on them through to March 11 and beyond.”
Morley MLA Ian Britza did not respond to questions sent by the Eastern Reporter.
There were no One Nation candidates running for the seats of Maylands, Bas-sendean, Morley, Mirrabooka, Mt Lawley or West Swan.
Christopher Fernandez and Lloyd Mcintosh will run for One Nation in the East Metropolitan Region in the Legislative Council.