Crossbench MP Bob Katter has warned Bill Shorten that he will likely suffer if Labor is successful in its bid to set up a new Federal corruption watchdog.

The Opposition Leader is threatening to work with the crossbench to force the establishment of a national integrity commission before the end of the year, unless the coalition offers bipartisan support for the proposal.

Prime Minister Scott Morrison has been reluctant to create a Federal version of the Independent Commission Against Corruption operating in NSW.

But his Government’s new-found minority status leaves it vulnerable to losing a vote on the floor of Parliament’s Lower House, where five of the six crossbenchers are publicly backing the push for an anti-corruption body.

Mr Katter, who could provide one of the two extra votes needed to force Opposition legislation through, said he would be “sitting on the fence on this one until the last minute” because a Federal ICAC could be a “two-edged sword”.

He said the Criminal Justice Commission set up after the Fitzgerald inquiry into Queensland Police in the 1980s had led to four Cabinet ministers who misused their ministerial allowances being jailed for “pedantic, petty irrelevancies”.

“There is a big downside to this and if the polls are correct, the biggest loser will be Shorten and his incoming ALP government,” Mr Katter said.

“I, of all people, know clearly the necessity for such a body, but also its downsides. While it sounds noble, that’s not the way these things end up.”

Mr Shorten, who announced plans for such a commission in January, said he had discussed Labor’s model with crossbench MPs ahead of the last sitting fortnight of Parliament for the year.

He believed there was an “appetite” across party lines for a national integrity commission, which he described as a “down payment” to ensure that Australians could have confidence in the political process.

“We will work with the coalition, but we will not wait for them,” Mr Shorten said.

“There are crossbenchers who equally support the proposal. I also believe there will be some members of the Government backbench, and perhaps even Mr Morrison’s frontbench, who don’t understand why the Government is dragging its feet on a national anti-corruption commission.”

Attorney-General Christian Porter has left the door open on a national anti-corruption body, but yesterday accused Labor of making policy on the run because of the lack of available detail on its plan.

“The Government continues to carefully consider the best way to further strengthen and improve the national integrity framework, and I am open to discussing all policy options,” he said. “It is important that changes in this area improve upon the current system, rather than adding complexity and confusion.”

However, Defence Minister Christopher Pyne said he did not believe a Federal ICAC was necessary. “It’s just another way of Bill Shorten trying to distract people from the real issues that matter,” Mr Pyne said.

The Greens’ Adam Bandt and independents Kerryn Phelps, Rebekha Sharkie, Cathy McGowan and Andrew Wilkie have already moved to set up a Federal integrity commission with wide-ranging powers over not only politics but also lobbyists, agencies and private contractors that deal with government.

Dr Phelps, whose victory in the Wentworth by-election cost the Government its parliamentary majority, believes a commission could be used “in the short term” and says she has already discussed a potential model with former judges.