The construction of a new Powerhouse Museum has been fast-tracked threatening the historic Willow Grove mansion.

The government’s plan includes relocating the mansion elsewhere in Parramatta to make way for the Powerhouse Museum.

Final planning approval was announced on Friday despite an ongoing inquiry into the demolition of the site.

Ray Hadley, who has been fiercely campaigning to save Parramatta’s historic Willow Grove and St George’s Terrace buildings, was left “non-plussed” by the approval.

“I don’t know why the Premier is intent on this sort of self-destruction,” Ray Hadley said.

NSW Shadow Minister for the Arts Walt Secord told Ray answers are needed.

“It caught me completely by surprise.”

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