Chief Minister Natasha Fyles needs to resign for breaching the public’s trust, the Opposition CLP says, following the NT Independent’s special investigation that revealed her secret shares in a mining company that presented a fresh undisclosed conflict of interest, while Labor is reportedly currently counting the numbers against the Chief Minister in the party room.

The NT Independent revealed on Monday that Ms Fyles had not publicly disclosed 754 shares she currently holds in South32, the company that runs the Gemco mine on Groote Eylandt, while refusing as Health Minister to investigate the suspected heavy metal poisoning of Indigenous Territorians on the island earlier this year.

The failure to divest the shareholdings breaches the ministerial code of conduct that forbids ministers from holding shares in companies that present a conflict of interest. The failure to disclose the shares publicly breaches the Legislative Assembly (Disclosure of Interests) Act.

Critics have said the latest revelations that Ms Fyles holds shares in another company she makes decisions about as a minister has affected the Territory’s reputation on the national stage.

Sky News reported on Monday afternoon that senior Labor figures have started counting the numbers against Ms Fyles, with one party source reportedly telling the outlet, “I’m not sure how she survives this”.

Perceived frontrunners to possibly replace Ms Fyles include Nicole Manison from the right faction of the party and Joel Bowden from the left faction.

A failure by the Labor caucus to unanimously pick a new leader would result in a vote of the party rank-and-file, under Territory Labor’s constitution, which could drag on for weeks.

Sky News reported sources saying Ms Fyles could resign as early as this week or possibly face a leadership challenge in the new year, if polling numbers revealed last month did not improve. Redbridge Group released results from a phone poll taken in mid-November that showed Territory Labor’s first preference support falling below 20 per cent.

Ms Fyles initially refused to respond to the NT Independent’s questions about the undisclosed shares, but her office reportedly told other local media outlets on Monday that she was interstate at a funeral and would not be commenting on the latest conflict of interest and the undisclosed shares until she returns on Tuesday.

She had claimed last month while defending her shares in Woodside Energy that she had “declared everything” on her Register of Members’ Interests and “regularly updated” the register to ensure any potential conflict of interest was managed and “so the public can see [the shareholdings].”

“You have to declare every single potential conflict,” she told ABC Radio on November 14. “I declare everything and then each conflict is managed…”

Opposition Leader Lia Finocchiaro said on Monday that Ms Fyles’ role as Chief Minister was “no longer tenable and she needs to resign”.

“She’s made a very serious decision not to investigate clear health issues on [Groote Eylandt] and yet at the same time has failed to disclose her financial interest in [the company that runs it],” Ms Finocchiaro said.

“This is clearly a breach of the public’s trust, if true, and she can no longer hold the confidence of our community to lead the Territory.”

Fyles making the NT the nation’s ‘laughing stock’: Environment Centre

Environment Centre NT director Kirsty Howey said Ms Fyles’ undisclosed shares in South32 while making decisions that affect the company was “deeply concerning” and questioned what other shares Ms Fyles has not disclosed that could further affect the Territory’s reputation.

“People around Australia will quite rightly be asking if the concept of ‘conflict of interest’ has any meaning at all in the Northern Territory,” she said.

“What other private interests does the Chief Minister – and other NT Government Ministers for that matter – hold that have not been disclosed?”

Ms Howey added that “at this stage, the Northern Territory is a laughing stock”.

“Basic rules of good governance and integrity appear to have been thrown out the window,” she said.

“That the Chief Minister appears to have been involved in government decisions about a mine operated by a company in which she owns shares is deeply concerning.”