OTTAWA -- One week after defeating Liberal Leader Justin Trudeau's attempt to open MPs' expenses to public scrutiny, the NDP has come up with a proposal of its own.

New Democrat MP Peter Julian has tabled a motion aimed at creating an independent body to oversee House of Commons spending, including MPs' expenses.

The new oversight body would replace the secretive board of internal economy, a multi-party committee that is currently responsible for the financial administration of the Commons.

Julian says the idea is to enhance transparency and ensure that MPs are no longer in charge of policing themselves.

But whereas Trudeau's proposals -- dismissed by the NDP last week as a "stunt" -- would have taken effect immediately had he won unanimous consent, Julian's proposals could take almost a year to produce any result.

His motion will not be debated until the fall; if it passes, it calls for public hearings -- involving the auditor general and the Commons chief financial officer -- to examine the creation of a new oversight body.

It anticipates that any resultant changes to the disclosure and reporting of MPs' expenses would not be implemented until April 2014.

The NDP says it has been working on the proposals for over a year.

"We hope the Conservatives and the Liberals will look at this proposal seriously," Julian said in a written statement.

"It's time to have a serious debate about this issue. We need to move beyond stunts and political games."

Conservatives supported Trudeau's attempt last week to require MPs to publicly post their travel and hospitality and office expenses quarterly, among other things. New Democrat MPs denied unanimous consent so his effort failed.

Trudeau has said Liberal MPs will begin posting their expenses online in the fall, regardless of what other parties choose to do.

Julian said the NDP is deliberately taking its time because the matter is too serious to be dealt with "at a moment's notice," as Trudeau tried to do.

"It gives members of Parliament a chance to think about it over the summer," he said in an interview.