Tony Abbott was asked to register as agent of foreign influence after migration speech in Hungary

Tony Abbott was asked to consider registering as an agent of foreign influence for speaking at a conference organised by the Hungarian government, at which he gave a controversial speech on migration and praised the country’s far-right prime minister, Viktor Orbán.

The revelation is contained in documents released under freedom of information laws after the Institute of Public Affairs investigated why Abbott was also asked to register under the foreign influence transparency scheme for an address to the Conservative Political Action Conference (CPAC).

The documents reveal Abbott’s office was in discussion about the possible need to register for months and missed a self-imposed deadline to sign up to the register for foreign entities and their agents to declare when they are seeking to influence Australian politics.

An aide told the Attorney General’s Department on 22 October that the former prime minister was “happy to register if [CPAC] is found to be a registerable event” despite later complaining publicly the suggestion he do so was “absurd”.

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The first CPAC Australia conference, held in August, boasted Abbott, Liberal senator Amanda Stoker, former deputy prime minister John Anderson and Liberal candidates Warren Mundine and Jacinta Price among its speakers.

Founded by the American Conservative Union, the conference is closely affiliated with the US Republican party and is set to become a regular feature of the Australian political landscape with plans for another conference in August.

The documents reveal the attorney general’s office was informed in August about the organisers of CPAC, LibertyWorks, being contacted about their obligations. They were told that five speakers might need to register as a result of their participation at the conference, including Abbott.

Talking points drafted by the Department for the Attorney General on 2 August suggest that, if asked, Christian Porter might reply that his department “has written to the president of LibertyWorks, Mr Andrew Cooper” drawing his attention to the scheme and seeking his cooperation “to ensure those speaking at the conference are also aware of the obligations imposed by the scheme”.

The documents suggest that after the 9 August conference, registrations “should have been lodged” within a fortnight.

Multiple emails and file notes indicate that on 30 August Abbott’s office promised the attorney general’s department he would complete a registration “shortly”.

One email recorded that an Abbott staffer had verbally advised that Abbott was on leave for a week and “a registration would be completed on Mr Abbott’s return with respect to CPAC”.

Lucinda Atkinson, the assistant secretary of the department’s transparency frameworks section, wrote to Abbott on 15 October noting it had “not yet received your registration”.

“I also seek your cooperation to consider whether you may have further registration obligations in relation to activities you have undertaken subsequently, including your address to the Budapest Demographic Summit in early September, a forum which we understand was hosted by the Hungarian government.”

Related: Tony Abbott doubles down on praise for Hungary's far-right PM Viktor Orbán

In that speech Abbott praised Orbán, warned about “military age” male immigrants “swarming” Europe and accused the left of attempting to undermine western society with migration and the “climate cult”.

LibertyWorks disputed the need to register, arguing there was no input from the US government in the CPAC conference, resulting in a further email on 22 October in which a public servant noted it was “reasonable” of Abbott to hold off until the issue was resolved and proposing the department follow up in a month.

“[Redacted] indicated he [Abbott] would be happy to register if it is found to be a registerable event,” it said.

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On 2 November, the Australian reported that Tony Abbott and LibertyWorks had been asked to register as “agents of foreign influence” which Abbott labelled “absurd” and had reportedly “angered” Porter.

“I have made it clear to my department that I expect it to demonstrate a focus on the most serious instances of noncompliance,” Porter reportedly said.

In January, the Liberal senator James Paterson claimed Labor’s shadow attorney general, Mark Dreyfus, had encouraged the department to investigate CPAC.

The documents show that on 22 July Dreyfus had “queried the application of the scheme to foreign political organisations holding events in Australia”.

“He specifically raised the upcoming [CPAC event] … as an example of an event that may trigger registration obligations under the scheme and asked what the department planned to do about it”.