South Korean pop star Hanni has made a surprise announcement, saying she will testify to the country's National Assembly in a hearing about bullying in the music industry.

The singer, who is part of the girl group NewJeans, said she had made the decision without telling her managers or her record label, Ador.

"I believe going forward is the right thing to do, no matter how much I think about it," she wrote to fans on social media.

It comes after she and the other four members of her band raised concerns about their treatment by Ador during an impromptu YouTube livestream on 11 September.

The group were the eighth biggest-selling act in the world last year, scoring international hits with feathery, throwback songs like SuperShy and OMG.

However, their mentor and record label chief executive, Min Hee-Jin, was removed earlier this year over allegations that she had planned a hostile takeover that would make NewJeans and Ador independent of their parent label, Hybe. Min has denied the accusations against her.

In the band's YouTube video, which has since been deleted, they demanded Min's reinstatement; and made claims of workplace harassment.

Hanni said that when she greeted the members of another band at their record label offices, their manager had instructed them to "ignore her".

The 20-year-old reported the incident to Ador’s new chief executive, Kim Joo-Young - but said her concerns had been brushed off.

“She told me it was too late and that I had no evidence. Seeing her ignoring the issue made me feel like there was no one to protect us,” Hanni alleged during the livestream.

The accusation sparked a war of words between fans of NewJeans and the girl group Illit - who were rumoured to be the antagonists.

As the row escalated, the agency managing Illit, Belift Lab, was forced to issue a denial.

"Illit's managers never instructed anyone to 'ignore' NewJeans members, and the Illit members have always greeted NewJeans when passing by," the agency said.

Belift said they had reviewed a video that showed Illit's members bowing to Hanni on the day of the incident - but that footage of their subsequent interactions was not available.

The agency also denied claims from the parents of NewJeans members that this later footage had been deleted on purpose.

The row eventually caught the attention of South Korea's Environment and Labour Committee, who have summoned both Hanni and Kim Joo-Young to testify to an audit on workplace harassment later this month.

In her statement, Hanni told fans: "I've made my decision. I'm going to go the National Assembly. A parliamentary inspection!

"I'm going alone. They still don't know... neither my managers nor the company."

The singer thanked fans for their support, and reassured them that they don't "need to worry".

"I'm doing this for myself and for the members [of NewJeans], and also for the Bunnies [fans]," she added.

"No, it's not difficult. I want to do this."