Stephen Harper is making it clear there's pretty much nothing that will keep him from balancing the federal budget this fiscal year.

The prime minister has slammed the door on the possibility the government would open the vault for a stimulus program to help the economy — which has been weakened by lower oil prices.

Former Liberal prime minister Paul Martin took aim at the Conservative fiscal record in an interview with CBC Radio's The House on the weekend, calling for a stimulus program to lift the economy.

Speaking in North Vancouver, Harper said it makes absolutely no long-term economic sense to launch a major stimulus program that would drive the country back into deficit when the economy is still growing, albeit at a slower rate.

Harper's remarks come shortly after the government unloaded its multibillion-dollar stake in General Motors.

The sale Monday of 73.4 million GM shares is expected to help the Conservatives achieve their long-running pledge to balance the upcoming election-year budget.

Harper has repeatedly insisted the government will erase the deficit in the April 21 budget despite the oil slump — a promise that could be key to his re-election chances in the October vote.