The Australian Electoral Commission has confirmed it is reviewing whether Pauline Hanson's One Nation breached financial disclosure laws.
Labor has asked the Commission to investigate the party after its former Treasurer, Ian Nelson, alleged that money used to purchase a light plane was deliberately hidden from disclosure.
"This information is now being reviewed in the context of the disclosure provisions of the Commonwealth Electoral Act 1918," a statement from the AEC said.
It said any findings will be addressed "directly with the party" or "entity concerned" and refused to comment further.
The Jabiru aircraft is frequently used by Pauline Hanson's chief of staff, James Ashby, to fly the party leader around the country into regional areas.
Labor's Tony Burke said he can't see how not declaring the money for the purchase could be an "inadvertent" oversight.
"It is difficult to see how this is anything other than a deliberate omission, and a deliberate omission to the tune, if this aircraft had been new, of something in the order of $100,000," Mr Burke said.
Watch: Tony Burke's take
Former Queensland One Nation treasurer Ian Nelson told the ABC's Four Corners program he urged Senator Hanson and Mr Ashby to declare the plane as a gift, but was told not to worry about it.
The program also raised allegations of candidates being forced to sign contracts which committed them to spend money with Mr Ashby's printing company and imposed a $250,000 administration fee if they were elected to parliament but later quit the party.
Watch: Pauline Hanson's inaugural flight shared on Facebook
Special Minister of State Scott Ryan has spoken with the AEC commissioner Tom Rogers after the program went to air, AAP has been told.
"They will have a further conversation in coming days," a spokeswoman said.
However Labor senator Murray Watt has referred a possible breach of electoral laws to the AEC.
"A breach of financial disclosure obligations under the Act may be a criminal offence," Senator Watt said in the letter to the AEC.
"Furthermore, any attempt to subvert these critical measures, which seek to ensure transparency and accountability in campaign financing, threatens to undermine public confidence in our system of democracy."
Queensland One Nation state leader Steve Dickson said on Tuesday his party had met its obligations to declare donations.
"I can't give you all the details on how James has come by his plane - if he's bought it personally, if it's been a part of some sort of a donation - but what I can say is we are playing by the rules," Mr Dickson told Sky News.
Mr Dickson, a former Liberal National Party MP who quit to join Senator Hanson's party, described the ABC program as a "stitch up" featuring disgruntled former officials and candidates.
Watch: ABC's Four Corners prompts calls for investigation into One Nation finances
Asked how influential Mr Ashby was in the party, Mr Dickson said he was "an element of the organisation".
Greens democracy spokesperson Lee Rhiannon said there was a strong case for federal and state electoral commissions to investigate the political donations and gifts received by One Nation.
"How Senator Pauline Hanson has had access to a small plane for campaign purposes should have been reported," she told AAP.
Senator Hanson has declined to comment.
She told Sky News in January she provided fuel for the aircraft out of her own pocket.
"I've still got my plane, well the party's plane, but all the trips I've done in that since the election I've filled it up myself," she said.
One Nation declared a payment of $1187 noted as "Jabiru aircraft service" in its Electoral Commission of Queensland party disclosure return for the first half of 2016.
The disclosure return was signed by Senator Hanson's brother-in-law Greg Smith, who the form said was the "party agent".
Mr Ashby told Sky News in a brief statement on Tuesday his company had bought the plane.
"It's the second plane I've owned. I'm very capable of buying my own planes. The hours used for the party have been declared."
The aircraft is registered to Mr Ashby through Recreational Aviation Australia.
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-With AAP
