Canadian prime minister Justin Trudeau, dogged by accusations that rich donors to his Liberal Party gained privileged access, will be questioned by the ethics commissioner to see whether he broke conflict of interest rules, an official said on Thursday.

Mr Trudeau, who came to power in November 2015 vowing to run an open and ethical government, is facing relentless accusations that the Liberals are running a cash-for-access scheme.

"I will follow up with Mr. Trudeau regarding his involvement with the fundraising events," Ethics Commissioner Mary Dawson said in a letter to Rona Ambrose, interim leader of the opposition Conservative Party, who had filed a complaint.

Jocelyne Brisebois, a spokeswoman for Ms Dawson, said she did not know when the conversation would take place.

Mr Trudeau has been under pressure for weeks about revelations that Liberal donors enjoyed privileged access to fundraising events where the prime minister and cabinet members spoke.

In remarks to reporters after the news broke, Mr Trudeau mantained that he had done nothing wrong.

"We will always work with the ethics commissioner and anyone else who has questions of this government," he said.