Prime Minister Kevin Rudd and Federal Treasurer Wayne Swan have given Opposition Leader Malcolm Turnbull 24 hours to produce an email at the centre of political misconduct allegations.

The Federal Opposition is demanding Mr Swan step down, saying he has used his position to seek special treatment for Queensland car dealer John Grant, a friend of Mr Rudd's.

But the Federal Treasurer says he will not resign over the allegations that he misled Parliament and has dismissed reports that his position hangs in the balance as "ridiculous" and "absurd".

The Government is trying to increase the pressure on Mr Turnbull about the email that he says shows the Prime Minister also misled parliament about the issue.

The Government says the email is a fake and the Australian Federal Police (AFP) have been called in to investigate.

Mr Rudd says the email must be produced to Parliament tomorrow so its authenticity can be verified.

"If when Parliament resumes in 24 hours Mr Turnbull fails to produce this email, this email upon which his entire case against the Government is based, for authentication, he has no alternative but to stand in the Parliament, apologise and to resign," he said.

"Mr Turnbull has the clock ticking."

Mr Swan also says the pressure is now on Mr Turnbull to provide any evidence.

"He's got some very serious questions to answer about his role in this email, or this fake email," Mr Swan told Channel Nine.

"What knowledge does he have of it? Where did he see it? Who did he get it from? And if he can't produce that then he should resign."

>> Read more on Swan's involvement (ABC via Yahoo!7 NEWS)