Scott Morrison has brushed off questions about Gladys Liu, despite taking to Chinese social media platform WeChat to defend the embattled Liberal MP and to claim he stands up for “all Chinese-Australians”.

On Friday the controversy around the member for Chisholm grew after the Herald Sun reported that Liu had not filed a return declaring a $39,675 donation to the Victorian Liberal party in 2015-16.

Labor has targeted Liu for failing to disclose her membership of Chinese government-linked associations before her preselection to the Liberal party, which Morrison has labelled a “grubby” tactic.

At a visit to the Binna Burra Lodge to survey Queensland fire damage, Morrison was asked why it was “racist” to question Liu’s associations and whether it was racist of him to have labelled Labor’s Sam Dastyari “Shanghai Sam”.

Morrison told reporters: “I didn’t use either of those phrases, so … I think people here today are focused on the fires, not Canberra.”

According to transcripts on the Treasury website, Morrison referred to Dastyari as “Shanghai Sam” on at least three occasions in September 2016 at the height of the former Labor senator’s donations scandal, repeating the epithet and calling on Dastyari to resign on Sky News, FiveAA and 2GB Radio.

On Thursday evening Morrison posted a video of his defence of Liu in question time on WeChat with the caption: “Gladys Liu has overcome many obstacles in his life and became the first Chinese woman to be elected to the House of Representatives.”

Screenshot from Scott Morrison WeChat account defending Liberal MP Gladys Liu Photograph: Scott Morrison WeChat

“The Labor party is sparing no effort to discredit Liu, but I will stand up and defend her and all Chinese-Australians because they have made great contributions to Australia with a sincere heart.”

Although Morrison has so far refused to say if he has received an intelligence briefing about Liu, the former president of the Victorian Liberal party, Michael Kroger, has rejected suggestions the party had been warned by security agencies that it would be “unwise” for her to run for parliament.

The former Labor foreign affairs minister and now chancellor of the Australian National University, Gareth Evans, has also criticised the level and tone of media coverage, describing it as a symptom of “hyper-anxiety” about China.

Evans told the Asian-Australian Leadership Summit on Thursday that the “bamboo ceiling” limiting the rise of Asian-Australians to positions of power is real, and the “saturation coverage in the media this week” is a reminder of obstacles faced by Chinese-Australians in particular.

“The current environment of hyper-anxiety in some quarters about baleful Chinese – and particularly Chinese Communist party – influence is making it harder than it has ever been for Chinese-Australians to aspire to leadership positions, or indeed any position at all in fields that are seen as even remotely security-sensitive, not least in the public service,” he said.

“It is an environment that bears no relationship to the objective evidence we have that such influence as has been sought, in our universities, politics, public administration and elsewhere, has been of a minimal and marginal nature.

“And it is one which utterly misrepresents the reality of the overriding loyalty which Chinese-Australians have always had to this country and will continue to have. It’s an environment of anxiety and fear that has to stop, and stop fast, or we will all be diminished by it.”

Penny Wong, Mathias Cormann and Kristina Keneally in a heated exchange in the Senate yesterday over allegations of racism and the Gladys Liu matter: "It's incomprehensible that Senator Wong, as a Chinese-Australian, would perpetrate a smear on herself". pic.twitter.com/QXbBiUvkmf — Guardian Australia (@GuardianAus) September 13, 2019

On Friday the shadow attorney general, Mark Dreyfus, told Radio National “the only person linking these serious concerns to the whole Chinese-Australian community is Scott Morrison”.

When asked about Evans’s comments, Dreyfus said Labor’s leader in the Senate is Penny Wong, rejecting suggestions the opposition’s attack has broader implications for the Chinese-Australian community.

Dreyfus said Morrison hoped to “hurl a false, disgraceful allegation of racism” to avoid scrutiny.

“Every day this scandal deepens and there are more revelations,” he said. “The [prime minister] can stop this and he should stop this by coming into the parliament and making an explanation, and so too should the recently elected member for Chisholm, Gladys Liu.”

Dreyfus questioned whether Morrison had been briefed about Liu and whether he had “put his party interests in winning a marginal seat ahead of the national interest” He said Liu was yet to explain which organisations she was a member of, what she did for them, if and when she resigned from them.

The Victorian Liberal party’s annual return to the Australian Electoral Commission for 2015-16 declares a $39,675 donation from Liu.

The Herald Sun reported the money was for a $24,175 auction item at a fundraiser and a separate $15,500 donation to the party, and follows a similar lapse of failing to declare a $25,000 donation in 2014 for three years.

Liu’s alleged ties to the propaganda machine linked to the Chinese government were first reported by the ABC, which revealed a Chinese government online record listed her name as a council member of the Guangdong provincial chapter of the China Overseas Exchange Association between 2003 and 2015.

The association was an arm of the Chinese government’s central political and administrative body, and has since been merged with the Communist party’s propaganda arm, the United Front Work Department.

The controversy was sparked by a Sky News interview in which Liu said she could not recall if she was a member of the group and struggled to answer questions about China’s activities in the South China sea.

Dreyfus argued that when Labor’s Sam Dastyari failed to back the bipartisan position on the South China sea, Morrison had accused him of betraying Australia.