Canada’s big city mayors are urging the federal government to keep billions of dollars in infrastructure money flowing as the country enters a new era of restraint.

They want Ottawa to extend the $4-billion federal infrastructure stimulus fund for at least six months past the March 2011 deadline — and consider more funding even as it looks to save money elsewhere.

They’re also urging the feds not to cut other programs — including the gas tax fund and GST rebates — that help municipalities build and repair roads, bridges, sewer systems and other infrastructure.

The mayors argue spending on infrastructure will actually help the government erase the $56-billion deficit racked up since last year’s recession, creating jobs, spurring economic growth and generating revenue to fill federal coffers.

“The best way to fight federal deficits is to have people working and paying … taxes,” said Toronto Mayor David Miller. Regina Mayor Pat Fiacco agreed infrastructure funding “more than pays for itself.”

The mayors made their pitch as federal Finance Minister Jim Flaherty prepares to unveil a budget March 4. Among other things, the budget will launch a review program to identify spending that can be cut as the government attempts to return to balanced books.