The Premier made the shock decision to remove Ms Cusack from her position as parliamentary secretary for the Hunter after crossing the floor to vote against the controversial koala (Local Land Services) bill.

It was the same bill that almost tore apart the Coalition in September when Ms Berejiklian stared down a threat from deputy leader John Barilaro to move National Party MPs to the crossbench over the koala protection laws.

Ms Cusack's vote means that the bill would have to be torn up and restarted at a later date.

The public spat between the Premier and Ms Cusack is nothing new. During the March 2019 election campaign Ms Cusack was removed from her parliamentary secretary's role before being reinstate late last year, and was later reprimanded after Ms Cusack had announced that the $188 million Fingal bypass road election promise would not be honoured.

Both Premier and Ms Cusack would not comment on Thursday's sacking when contacted this week.

Ms Washington, however, was quick to make her feelings known. "There is no love lost between Catherine Cusack and I. Her behaviour towards me at the last election was appalling, but her decision last week was the right decision. Thank you, Catherine, for standing up to protect our koalas," Ms Washington said.

The Nature Conservation Council has also applauded the principled decision by Ms Cusack in blocking the bill. "It is far better to go back to the drawing board on koala laws than to accept the Nationals' koala-killing bill," said chief executive Chris Gambian.

"But already the decision to revert to the old koala planning arrangements shows that the battle to protect NSW koalas is far from over. The furore over the new planning policy is an ideological obsession and not grounded in an actual problem and the weakening koala protections is at odds with the government's stated aim of doubling koala numbers by 2050."

In her parliamentary address on the LLS amendment bill last Thursday night, Ms Cusack made reference to fragile koala numbers and their significant decline over many years.

"We know that the region lost an estimated 71 per cent of its already endangered koalas during the Black Summer fires. Our koalas are in so much trouble and their plight is really well understood by my community.

"My community is incredibly distressed by this legislation. In all of the communications sent to me on this issue, I have not had a single person ask me to vote for this bill, not one.

"I cannot find a constituency for this legislation. All I can find is enormous distress and mistrust."

She said that she was not party to the processes that brought the bill to the House. "I cannot be held accountable and nor can I have any faith in that process, which has zero to do with protecting koalas. It is to try to patch-up a political disagreement."

Ms Cusack moved an amendment to the bill "in the earnest belief that a more transparent process will assist the bill, the government and the community to come together in the great cause of saving our koalas. There is nothing to fear from an all-party inquiry."

The last time Ms Cusack lost her secretary's position,Upper House MLC Taylor Martin was given the job of spokesperson for the state seat of Port Stephens. Mr Martin would not comment when contacted on Tuesday.