"After having committed to making the parliamentary budget officer 'truly independent of government,' it is disturbing that political staff from your office — the highest government office in Canada — would seek closed-door meetings with the PBO," Mulcair and Caron wrote. "These sorts of backroom meetings are out of place when it comes to an office that plays such an important accountability role and jeopardize the independence of the office of the PBO."

NDP leader Tom Mulcair and Guy Caron, the party's finance critic, have written to Prime Minister Justin Trudeau to express concern about what the New Democrats describe as "inappropriate meetings" between members of the Prime Ministers Office and the parliamentary budget officer.

NDP Leader Tom Mulcair speaks in the House of Commons on Parliament Hill on Thursday, May 5, 2016. (Photo: Adrian Wyld/CP)

Last week, in releasing a draft bill and discussion paper about updating and expanding its mandate, the PBO disclosed that it had been approached by officials in the PMO to discuss how the legislation governing the PBO might be changed to accommodate Liberal election commitments.

The New Democrats note that the PBO has a "clear responsibility" to assist MPs with the task of holding the government to account and stress that it is "essential that the PBO continues to report to Parliament as opposed to the prime minister directly."

In an interview, Jean-Denis Frechette, the parliamentary budget officer, says an official with the Prime Minister's Office initiated the discussion and that there were two meetings: the first in January, the second in April.

In January, there was discussion of how the PBO's mandate could be expanded to include the costing of party platforms, as the Liberals proposed during last year's election.

In April, Frechette says the PBO was asked to provide a vision for how the office could be made fully independent and provided with better resources.

Frechette says PMO's approach was 'pleasant surprise'

After the second meeting, the PBO provided the government with the draft bill. That draft and a discussion paper were then posted online after the former was leaked to a member of the media.

Frechette says it was a "pleasant surprise" when he was contacted because no one from the government or Parliament had previously reached out to discuss the Liberal campaign commitments.

The budget officer says he recognizes the NDP's concern, but that he is not sure how the conversation would have otherwise begun and that the legislation governing the PBO does not otherwise provide an outlet through which the PBO could raise issues with Parliament.

In their letter to the prime minister, Mulcair and Caron suggest that the finance committee evaluate the proposed legislation.

For its part, the Prime Minister's Office defended its discussions with the PBO.

"We were elected on a commitment to strengthen the independence of the PBO, a commitment reflected in our mandate letters," Cameron Ahmad, press secretary with the Prime Minister's Office, said in a statement. "Of course MPs, ministers, staff and officials should all be engaging with the PBO directly for their advice on how best to achieve this objective.

"We will not repeat the last government's mistake of refusing to have a positive dialogue with the PBO on how the government can enhance the openness and transparency of its finances for all parliamentarians."

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