The measures, which are also expected to give police greater ability to restrict the movements of purported extremists, will not be an assault on civil liberties, the prime minister said.
"These measures are designed to help authorities stop planned attacks, get threats off our streets, criminalize the promotion of terrorism, and prevent terrorists from travelling and recruiting others," Harper told a campaign-style event in the Ottawa-area.
"To be clear, in doing so, we shall be safeguarding our constitutional rights of speech, of association, of religion and all the rest."
Restricting the movement of suspects radicals can be done by lowering the threshold for obtaining a peace bond, a federal source, who asked to remain anonymous, told The Canadian Press last week.
In addition, the government wants to retool Canada's no-fly list procedures to make it easier to stop a suspected terrorist from boarding an airplane.
An internal federal review of last fall's deadly attacks on Canadian soldiers concluded there is a lack of suitable laws to crack down on radicals who openly encourage others to wage terrorism.
Michael Zehaf Bibeau shot Cpl. Nathan Cirillo, an honour guard at the National War Memorial, before storming Parliament's Centre Block on Oct. 22. Zehaf Bibeau was gunned down outside the Library of Parliament.
Two days earlier, a car driven by Martin Couture-Rouleau ran over and killed Warrant Officer Patrice Vincent in St-Jean-sur-Richelieu, Que., near Montreal. Police later shot and killed Couture-Rouleau when he advanced on officers with a knife.
Harper repeated for the partisan crowd that violent jihadism had declared "war" on the west, but painted it as a much wider problem than just the Islamic State, which has overrun vast parts of Iraq and Syria.
"Jihadi terrorists are destabilizing large parts of the globe," Harper said.
"In Asia and Africa, an increasing number of territories are becoming ungoverned and under their influence, attacks and plots outside these regions are becoming ever more frequent and dangerous in Australia, in France, in Belgium just recently, and of course here."
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