Christopher Pyne's new job has put his old boss, Scott Morrison, under pressure to reprimand him amid accusations it is a breach of ministerial standards.

Key points: The Statement of Ministerial Standards says that for 18 months after they leave office, former ministers will not lobby members of the Government on matters they had dealt with as a minister

The Statement of Ministerial Standards says that for 18 months after they leave office, former ministers will not lobby members of the Government on matters they had dealt with as a minister Senator Patrick said Mr Pyne's new role did not pass the pub test

Senator Patrick said Mr Pyne's new role did not pass the pub test He said Mr Pyne was hired due to his insider knowledge

Mr Pyne, who was defence minister until the election, on Wednesday revealed he has taken a job as a defence consultant with multinational business advisers EY.

"I am looking forward to providing strategic advice to EY, as the firm looks to expand its footprint in the defence industry," Mr Pyne said in a statement.

But Centre Alliance senator Rex Patrick has called on the Prime Minister to reprimand Mr Pyne for taking the position, which he argues breaches the Statement of Ministerial Standards.

It states that for 18 months after they leave office, former ministers "will not lobby, advocate or have business meetings with members of the Government … on any matters on which they have had official dealings as minister".

It also says ministers cannot "take personal advantage of information to which they have had access as a minister, where that information is not generally available to the public".

"I think what he's done does breach the code and I think this becomes a test for the Prime Minister," Senator Patrick told AM.

"It becomes a test for his conviction towards his own statement of ministerial standards.

"It's inappropriate and it doesn't pass the pub test."

Centre Alliance senator Rex Patrick said the possible code breach was a test for the Prime Minister. ( ABC News: Nick Haggarty )

Senator Patrick said Mr Morrison should urgently call Mr Pyne.

"And if he gets nowhere he should direct Defence and other government agencies to cease awarding any contracts to EY until the 18-month time period specified in his ministerial standards has expired," Senator Patrick said.

He added there was "no question" EY took on Mr Pyne because of his insider knowledge.

"This will raise probity issues with other companies rightfully concerned with the advantage EY now has," Senator Patrick said.

"I'm of the view Mr Pyne would not pass on any sensitive information, but he can't unknow what he knows when he's forming up advice to give EY."

Professor John Wanna of Australia National University told AM large business consultancies were targeting government defence spending as a source of revenue growth.

"Defence is the largest Commonwealth procurement program and so this is where there is ample amounts of money, it is multi-year money," he said.

But he added the Statement of Ministerial Standards was difficult to enforce properly.

"Though the wording is that they can't lobby and they can't divulge information, nothing stops them from working with others, in this case Ernst and Young, to advise them on what they should be saying when they go and lobby."

The ABC contacted Mr Morrison's office to ask if he thought Mr Pyne had breached ministerial standards.

A spokesman said the rules were clear around what ministers could do when they retire and referred the ABC to Mr Pyne's statement.