A police investigation into an alleged fake document used in a political attack by cabinet minister Angus Taylor has been referred to the Australian Federal Police.
Mr Taylor's office in November used the document to attack the travel expenses of Sydney lord mayor Clover Moore.
A spokeswoman for Mr Taylor said the minister would cooperate fully with the AFP investigation.
"Although he fully expects they will conclude that this matter is baseless," the spokeswoman said.
The NSW Police financial crime squad launched a strike force to investigate whether "any criminal offences" were committed in the document's creation.
They have now referred the investigation to the AFP.
"Following an investigation by the state crime command's financial crimes squad, the matter has been referred to the Australian Federal Police," a spokeswoman said in a statement to AAP on Thursday.
The AFP later on Thursday confirmed the referral from NSW Police "in relation to the alleged doctoring of a document" on December 20.
NSW Police had confirmed with Mr Taylor's solicitors it had concluded its investigation, his spokeswoman said.
"This supports his repeated previous statements that neither he, nor any member of his office, altered the document in question."
Prime Minister Scott Morrison has been criticised for contacting NSW Police Commissioner Mick Fuller to discuss the case.
A spokesman for the prime minister told AAP on Thursday it would be inappropriate to comment on a police investigation.
The letter Mr Taylor sent to Ms Moore criticised her for driving up carbon emissions by spending over $15 million in council money on domestic and international travel, but the figures were false.
The 2017/18 council report currently available online, as well as previously cached versions, shows international out-of-pocket travel costs such as meals and taxis were only $1728, and domestic costs were $4206.
The minister has apologised to Ms Moore but has not explained where the numbers came from.
The Department of Environment and Energy's original draft of the letter for Mr Taylor didn't include any mention of the council's travel figures.
It is alleged the false travel spend was added by the minister's office before being sent.
Opposition Leader Anthony Albanese said it was a "serious issue" and maintained he wanted Mr Morrison to take action against Mr Taylor.
"Suffice to say, I think you look at what was said and compare it with what clearly the facts are around this document and its creation and it being given to the media, and the two things don't add up," Mr Albanese told ABC TV.
"It is an issue - misleading a parliament and whether ministers are accountable or not and under the Westminster system. If you mislead parliament you lose your position."
Australian Associated Press
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