The Liberals have asked all federal government departments to come up with a plan to cut at least five per cent from their budgets to help fund items Prime Minister Paul Martin promised in the spring election campaign.

Some departments have been asked to find an even bigger chunk of money, says a senior source at Foreign Affairs – and the exercise risks slicing into programs the Martin government is publicly classifying as priorities in Tuesday's throne speech.

"The departments have been asked to provide savings equal to five per cent of their budget by Oct. 12, and this will provide a menu of choice for the expenditure review committee," Revenue Minister John McCallum, who is in charge of the expenditure review, told the CBC Monday.

He said government services and jobs won't be affected by the process, however.

"There's no cut to the size of government. The size of government will remain unchanged. It's about saving in some areas to put back into the priority areas such as in our election platform."

Staff at Foreign Affairs are privately saying they won't be able to increase Canada's profile abroad, as the throne speech will pledge to do, given the new financial reality they're facing.

They've been instructed to look for $74 million in savings over the next three years – a figure that represents slightly more than the five per cent all departments have been asked to find.

Sources at Foreign Affairs say that would leave them without the funding necessary to perform their current functions, let alone take on new projects.

They warn that both jobs and services overseas would be affected and the amount of foreign aid Canada provides would have to be reduced.