OTTAWA - The Defence Department may not be heading back into the old decade of budget darkness, but it could be in for a time of twilight.

The military will make it home from the war in Afghanistan just in time to take a lead role in the battle against the federal deficit.

Figures released in Finance Minister Jim Flaherty's budget on Tuesday show he's relying on the Defence Department to rein in spending sharply.

He expects Defence to account for up to 26 per cent of the federal government's anticipated $2 billion in spending cuts next year.

That figure jumps to 35 per cent in both 2013 and 2014 -- or $1 billion a year.

"The Defence Department is accounted to make up for a lot of the savings. In some years it's about a third of the overall savings," said Douglas Porter, deputy chief economist at Bank of Montreal.

The former Liberal government's deficit fight hit the military to the point that a top general dubbed the period "the decade of darkness."

"It's probably not quite as intense as what we went through in the 1990s, but it's not that different," Porter said. "It will certainly be a pretty serious degree of restraint on the defence sector."

The Conservatives, who've made hay out of supporting the military and still plan to spend billions on stealth fighters, often lamented the Liberal cuts to Defence.

The new restraint, beginning next year, coincides with the end of major combat in Kandahar.

Government supplementary estimates tabled earlier suggest that reduced overseas operations will save Defence as much as $300 million a year starting in 2012, although it's not clear how much of that is attributable to the changed Afghan mission.

The government announced in the 2010 budget that the military would contribute to the deficit fight, but the numbers have become more stark.

Porter said there's a certain volatility in the defence projections because, as the Libyan crisis has demonstrated, no one can predict how and when the military will be deployed.

The Harper government's anticipated savings flow out of a strategic review the government started last year.

Federal officials say another round of restraint is in the works and every department is being asked to prepare budget cuts of either five or ten per cent.

The federal Treasury Board will make the final call.

Porter said the federal government is in for years of profound belt-tightening.

He noted the overall spending reduction targets are certainly "doable" but they mark a drastic slowdown compared with recent years.

"It will require year after year of rounds of discipline," he said.

Budget documents call the restraint measures at Defence "a key element" of the plan to wipe the anticipated $29.6 billion deficit for 2011-12 off the books.

Starting next year, there will be cuts to "redundant and outdated equipment" and to the procurement system, which is already short of program officers, will be streamlined.

The department has struggled with big-ticket purchases -- such as new supply ships -- partly because of a lack of planning staff.