The new NSW Deputy Premier, John Barilaro, is at the centre of explosive claims that he and his party accepted illegal political donations from his wife, who Labor says is a property developer.

Just more than 24 hours after he became the leader of the Nationals in New South Wales, the State Opposition referred to documents in Question Time showing Mr Barilaro's wife Deanna donated to the National Party for three years in a row, despite being the director of two property development firms that Mr Barilaro himself had previously run.

Political donations from property developers have been banned in NSW since 2010.

Mr Barilaro was listed as a recipient of some of those donations on disclosure forms.

The documents show that in 2012, after Mr Barilaro was elected to Parliament, he resigned as director of two firms, Kotsabola Group and Euro Partners, and his wife Deanna was appointed director.

Mr Barilaro lists the "principal objects" of the two companies on his own parliamentary pecuniary interests forms as "property investment/development".

Disclosures of political donations returns for the 2013–14 financial year show Deanna Barilaro then donated $1,950 to the NSW Nationals.

In 2015 she donated a further $3,000 to the party.

Forms from 2016 show she donated $3,850 that year.

The total amount donated by Ms Barilaro during the period in question is $8,810.

Labor says all of those donations took place when Ms Barilaro was a director of Kotsabola Group and Euro Star partners, and therefore that she was a banned donor.

Barilaro surprised in Question Time interrogation

Mr Barilaro appeared taken aback when Labor raised the issue in Question Time.

"Have you accepted political donations from the director of a property development company?" Labor frontbencher Jodi McKay asked.

"All donations for candidates are made through our party organisation and as far as I know, I'm not sure what they are referring to," Mr Barilaro said.

When asked to confirm that the companies Kotsabola Group and Euro Partners were property development companies, Mr Barilaro said the Opposition's questions about donations were matters for the party organisation.

Labor's deputy leader Michael Daley demanded Mr Barilaro answer the question.

"They were your companies, if you don't know those answers who does?" he said.

Nationals say Barilaros were 'not property developers'

The NSW Nationals released a statement after Question Time saying they had reviewed the issue before last year's state election:

Prior to the 2015 election the NSW Nationals made a determination that Mr Barilaro and his wife Deanna were not considered property developers under the Expenditure and Disclosures Act. Under NSW Law the onus is on Political Parties to determine whether a donor is a prohibited donor. We have reviewed that determination again today and we stand by our assessment.

The ABC is seeking a response from Mr Barilaro.

Barilaro company documents and donation records

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