(CFRA) -- The Federal bureaucracy will be the focus of cuts in today’s Federal budget.

Finance Minister Jim Flaherty warns the “majority of the spending review reductions relate to back-office operations in government,” adding programs and services to Canadians will be mostly left untouched.

Reports say the Federal Conservatives budget will announce about $7 billion in annual savings in discretionary spending by the 2014-15 fiscal year.

Some experts have estimated cuts to discretionary spending will translate to 60-thousand public sector job losses, through sources say attrition will cover most of the losses.

CTV News reports up to 30-thousand jobs will be cut, but most will be lost through attrition.

NDP leader Thomas Mulcair told the NDP caucus on Wednesday that Prime Minister Stephen Harper will “have a fight on your hands” if the pre-budget signals bear out.

The budget will seek to curtail long-term spending by slowing the growth of Old Age Security, and reports suggest Flaherty will give notice to public service unions they must pay more for their indexed pension plans.

The House of Commons is set to rein in spending, with an all-party committee voting to decrease MPs office expenses by almost seven per cent over the next three years.

This will be the first budget from a majority Conservative Government.