Aboriginal and Torres Strait Islander Commission (ATSIC) representatives are a step closer to going to the High Court over the abolition of the Indigenous body.

A delegation of commissioners, including the chairman, Geoff Clark, met with David Jackson QC in Sydney yesterday.

Mr Clark says any challenge would focus on whether the creation of the Aboriginal and Torres Strait Islander Service (ATSIS) - set up to handle ATSIC's financial affairs - was legal.

"We'll challenge taking away the actual power from ATSIC to create ATSIS, to also further abolish ATSIC in this manner. We're challenging the process," he said.

South Australia's ATSIC representative, Klynton Wanganeen, says he has contacted all but three of its 18 members by phone informing them of legal advice obtained in Sydney yesterday from David Jackson QC.

Mr Wanganeen says the High Court challenge will argue that the creation of the Aboriginal and Torres Strait Islander Service (ATSIS) - established by the Federal Government to handle ATSIC's financial affairs - is unconstitutional.

"It's welcome news to the commissioners," he said.

"We believe we've been treated shabbily.

"We've always said from the word go that we don't really want to be in court but we had to protect an organisation that was being dismantled around us."