OTTAWA — The Prime Minister's Office is unfazed by calls from an international legal body that it owes an apology to the Supreme Court's chief justice for criticizing her in public.

Prime Minister Stephen Harper and Justice Minister Peter MacKay in May accused Chief Justice Beverley McLachlin of acting inappropriately when she attempted last summer to flag a potential legal problem to MacKay, relating to Marc Nadon, a federal court judge the government wanted to appoint to the top bench.

Ultimately, Nadon was deemed ineligible for the appointment, but the spat between the feds and top court led many in the Canadian legal community to call on Harper and MacKay to apologize.

A handful of Canadian lawyers penned a letter to the International Commission of Jurists (ICJ) in early May, asking them to investigate the government's claims that McLachlin was wrong to have attempted to contact the government to discuss Nadon's appointment.

The ICJ reviewed the situation and concluded McLachlin hadn't acted inappropriately, levelling blame instead on Harper and MacKay.

"The ICJ has been provided with no evidence that the chief justice had any intention in alerting the minister of justice and the Prime Minister's Office other than to alert them to the possibility that a legal issue could arise with the nomination of a justice of the federal court," the ICJ says in its letter. "Nothing in international standards would render such contact inappropriate."

"The prime minister and minister of justice could best remedy their encroachment upon the independence and integrity of the judiciary by publicly withdrawing or apologizing for their public criticism of the chief justice."

Jason MacDonald, spokesman for Harper, told QMI Agency he'd seen the letter.

"We have seen the letter and noted it," he said. "I've got nothing further to add to your story."