NDP Leader Thomas Mulcair says he supports any measure that will reduce the threat of terrorism, but questions whether banning Canadians from travelling to regions controlled by terrorist groups would 鈥渕ake a big difference, practically speaking.鈥

Mulcair made the remarks after Conservative Leader Stephen Harper said Sunday that he would follow the lead of Australia and make it illegal to travel to 鈥渄eclared areas鈥 in foreign countries where terrorist entities such as ISIS are fighting and training.

Harper said during a campaign stop in Ottawa that "there is absolutely no right in this country to travel to an area under the governance of terrorists鈥 and that 鈥渨e're not under any illusion here what just about everybody going to an area like that is doing.鈥

Harper said there may be "certain, rare circumstances鈥 where Canadians have legitimate reasons to travel to such places under such legislation and that 鈥渢here will be exceptions in the law for those.鈥

The Conservatives have not said which regions would be declared no-go zones for Canadians, but Australia鈥檚 foreign minister has declared ISIS-controlled Al-Raqqa province in Syria and the Mosul district in Iraq off limits. Australians who travel to those regions face up to 10 years in prison.

Mulcair, who spoke to reporters in Vancouver, said that there is 鈥渧ery little evidence鈥 that such a law could have a 鈥渃oncrete effect.鈥

The NDP leader chided Harper for not 鈥渄oing something concrete about radicalization of youth here in Canada,鈥 when it introduced it Anti-terrorism Act, known as Bill C-51. The NDP voted against C-51 citing civil liberties concerns.

Mulcair said 鈥渨e can all be a little skeptical as to whether or not there鈥檚 any real effect,鈥 considering that the proposed law was announced during the election campaign.

鈥淚 don鈥檛 know of too many flights between Toronto and these war zones,鈥 Mulcair added. 鈥淢ost of them are going through other countries, so it won鈥檛 make a big difference practically speaking.鈥

Security analyst Michael Zekulin told 麻豆影视 Channel that those going overseas to aid terrorist groups like ISIS are 鈥渁lready making every effort to ensure that their travel abroad is done surreptitiously鈥 and that keeping track of 鈥渨ho is going where and what they鈥檙e doing 鈥 has always been the problem.鈥

Zekulin said Canadians may question not only the enforceability of such a law, but whether a 鈥渞everse burden of proof鈥 is 鈥渁cceptable鈥 for those with legitimate reasons, such as research or news reporting, to travel in terrorist-controlled territories.

Ron Myles, a former CSIS agent, told 麻豆影视 Channel that it 鈥渟eems to be a bit of an oversight鈥 that such a law wasn鈥檛 part of earlier legislation because it has proven difficult to arrest people who return to Canada from ISIS-controlled zones.

However, Myles said it would be 鈥渆xtremely difficult to prove鈥 why a person travelled to such a place.

鈥淗ow do you prove what somebody did in a zone where you have absolutely no information, or very limited information, and take these people to criminal court?鈥 Myles said.

Myles added that would-be terrorists will find ways to take advantage of the exemptions, perhaps by disguising themselves as aid workers.

Liberal Leader Justin Trudeau, who spoke to reporters after a rally in Ottawa, said Canadians deserve to know more about how such a law might limit their rights, and that the announcement suggests, 鈥淢r. Harper wants to talk about anything except that his economic plan has failed.鈥