The political future of Associate Education Minister David Benson-Pope is in doubt as an inquiry gets underway into allegations he physically abused pupils as a teacher at Dunedin's Bayfield High School.

The inquiry request follows five former pupils of Bayfield High School going public with their stories, which support claims made by Act and National in parliament last week.

The claims include that Benson-Pope tied a pupil's hands and jammed a tennis ball in his mouth as a punishment and he gave another a bleeding nose.

Benson-Pope strongly refutes the allegations but stood down from cabinet pending the inquiry.

Prime Minister Helen Clark has asked the Solicitor-General to report back on options for an investigation, which her spokesman says could include a police, Queen's Counsel, or ministerial level inquiry.

Based on legal advice from Sandra Moran National's education spokesperson Bill English says David Benson-Pope had no choice but to stand down from cabinet. English says the situation for the minister doesn't look good.

Act leader Rodney Hide says Benson-Pope should be sacked from cabinet outright.

Following making the allegations in parliament last week Hide said he accepted the word of the associate education minister regarding his treatment of former pupils.

At the time Hide said he raised the issue after he was approached a number of times, but that he was prepared to take the minister's word that the incidents did not happen.

The Act leader said he spoke to those behind the claims after they were raised in parliament and told them if they were serious they should go public.

Prime Minister Helen Clark says she accepts Benson-Pope's word.

Education Minister Trevor Mallard will pick up the responsibilities left vacant by Benson-Pope including responsibility for the schools sector. Pete Hodgson will take over the ministers fisheries portfolio as acting minister.