Simon Birmingham the latest Liberal party frontbencher who will not campaign against Indigenous voice

Senator's show of reluctance comes after Julian Leeser resigned as shadow attorney general over referendum stance

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The Liberal frontbencher Simon Birmingham says he won't campaign against the Indigenous voice to parliament, becoming the latest opposition member to show reluctance to support the party's official position on the referendum.

Former Liberal minister for Indigenous Australians Ken Wyatt said some of his former colleagues were being tested" after the party's policy to campaign against the voice was revealed, as fallout continues from Julian Leeser's resignation from the opposition frontbench.

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