Limiting a ban on foreign donations to money flowing to political parties would create a “loophole” by still allowing donations to activist third-party groups, such as GetUp, the special minister of state has said.

Scott Ryan’s comments signal an intention to push on with a more comprehensive ban on foreign donations despite the fact Labor does not support extending the proposed ban to activist third-party groups.

Four Corners revealed details of donations from Chinese donors to the Labor and Liberal parties, including the allegation that the Labor senator Sam Dastyari contradicted party policy on the South China Sea a day after the Chinese billionaire Huang Xiangmo threatened to withdraw a promised $400,000 donation to the party.

On Wednesday the former United States director of national intelligence, James Clapper, warned of Chinese interference in Australian politics and called for a ban on foreign donations.

Ryan said that since the joint standing committee on electoral matters report in March he has been working on legislation to ban foreign donations, to be presented to parliament this year, but noted Labor and the Liberals were split on its reach.

“The government’s made clear that if we are going to ban foreign donations – as we should – it’s important ... that it’s got to be comprehensive,” he told Radio National on Wednesday.

“We don’t want to create a loophole where we look like we’re fixing a problem by saying political parties can’t accept foreign money but then create a loophole where foreign money can pour into third-party interest groups and others, who are just as politically active and have just as much influence over the political process.”

Ryan said Australia wanted to avoid the situation in the US where “there are great restrictions on political parties but money gets funnelled into third parties”, because it would mean one political ad could be paid for by foreign money and another couldn’t.

Asked whether the push for a ban conceded that foreign donations could influence policy decisions, Ryan said the rationale behind the ban was that “the Australian political process should [only] be subject to the actions of Australians”.

The special minister of state rejected the claim that the Coalition were targeting GetUp, which ran a vocal and influential campaign in marginal seats, and said he “didn’t want” to restrict their ability to campaign including handing out how-to-vote cards.

The Human Rights Law Centre and 15 nongovernment organisations launched a report, Defending Democracy, warning that Australian governments are seeking to restrict the free speech of not-for-profit organisations, through practices such as gag clauses in funding agreements and threats to hamstring advocacy groups’ ability to fundraise.

The report, released on Wednesday, argued that applying the foreign donation ban to NGOs would be “a step in the wrong direction” because it would harm community groups but fail to capture organisations like the Minerals Council of Australia, funded with membership fees not donations.

Clapper, a visiting professor at the Australian National University’s National Security College, told ABC AM that Australia should ban foreign donations because it was “hard to rationalise” why foreign entities and individuals should be able to donate.

Clapper warned that China is “seeking ways to influence, using many techniques, diplomatic, economic, military, that they haven’t done before” and likened China’s reach to Russia’s reported attempt to interfere with the US presidential election.

“The challenge we both face – the United States and Australia – is the potential jeopardy to the fundamental underpinnings of our political system.”

Ryan rejected the comparison, noting the allegations against Russia involved direct interference in the electoral process, something that had not been claimed in Australia.

Ryan also defended the former trade minister Andrew Robb – who took a contract with Chinese-owned Landbridge a day before he left office – by noting he had not breached the ministerial code of conduct. He said the current rules are “long-standing and strikes the right balance”.

On Tuesday Bill Shorten promised that Labor will not take donations from donors Australian resident Huang Xiangmo and the Australian Chinese citizen Chau Chak Wing, who were featured in the Four Corners program. He called on the Liberal party to do the same.

“I want direct and indirect foreign influence out of our elections,” Shorten said. “It’s now overdue for Malcolm Turnbull and the Liberal party to join with Labor to ban foreign donations.”