The Liberal government has given travellers from visa-exempt countries a six-month grace period to comply with a new pre-screening measure that was set to take effect on March 15, bowing to calls from industry representatives who expressed concerns over the timing of the new requirement.

Some three million travellers flying to or passing through Canada will be required to have what is known as an electronic travel authorization (eTA) prior to boarding their flight, according to the Department of Immigration, Refugees and Citizenship Canada.

The new requirement, a result of a 2011 joint border project with the U.S., is intended to make it easier and faster for low-risk travellers to come to Canada.

"However, from March 15, 2016 until fall 2016, travellers who do not have an eTA can board their flight, as long as they have appropriate travel documents, such as a valid passport," said a notice posted on the Canadian government web site Thursday.

"During this time, border services officers can let travellers arriving without an eTA into the country, as long as they meet the other requirements to enter Canada."

The new requirement applies to foreign nationals who don't normally require a visa to travel to Canada such as British, Australian and French citizens, among others, as well as permanent residents of the U.S. However, U.S. citizens and travellers with a valid Canadian visa are exempt from the new requirement. Canadian citizens, dual citizens, and permanent residents of Canada do not need to apply for an eTA.

Travellers can apply for an eTA online by answering a few questions and paying $7. According to the government, applicants will get their authorization within minutes of submitting the online form. The authorization is electronically linked to the person's passport and is valid for five years or until the passport expires, whichever comes first.

"We are very pleased with the leniency period the government extended to travellers," said Rob Taylor, a spokesperson for the Tourism Industry Association of Canada, in a phone interview with CBC News.

"Travellers will not be turned away at the airport, that's what we were looking for."

Advertising for eTA 'inadequate'

Taylor said there were concerns from the tourism and travel sector that the previous Conservative government had not done a good enough job of telling travellers about the eTA.

"The one challenge we've had is the government's communications strategy … which was in many cases inadequate," Taylor said on Friday.

There were also concerns that a newly-elected government with key departmental resources tied up in responding to the humanitarian crisis in Syria, would not be in a position to implement the new pre-screening measures during the upcoming spring break, a busy period for air travel.

"It was the cumulative effect and the ability to properly communicate it to potential travellers... that's what our biggest concern was," Taylor said.

As CBC reported earlier this week, the previous Conservative government had purchased $2.69 million in print and internet ads to raise awareness about the new eTA.

The Department of Immigration does plan to purchase another media ad buy to promote the eTA but it won't include mention of the six-month reprieve, a spokesperson confirmed with CBC today.

"Any future advertisements about eTA will continue to be focused on raising and sustaining general awareness of the new requirement and will not address the leniency period," said Nancy Caron, a spokesperson with the immigration department, in an email to CBC News.

"Timing of the 2016-2017 portion of the campaign will be confirmed following the completion of the 2015-2016 campaign and development of a new media plan."

The most recent ads began rolling out on Feb. 15, she said.

Concerns about a 'spaghetti of rules'

But what will happen to visa-exempt travellers once the six-month reprieve ends is unclear at this point.

Richard Kurland, an immigration lawyer and policy analyst, says foreign nationals who live in Canada as permanent residents could be sideswiped by the new entry requirement.

According to Kurland, the rules and exemptions are more complex than officials would have would-be travellers believe.

"It's a spaghetti of rules that are not easily understood by lawyers, let alone members of the public," Kurland said in a phone interview with CBC News on Friday.

Kurland said visa-exempt travellers who live in Canada as permanent residents could find themselves stranded in an overseas airport unless the rules change between now and the fall.

What's more, Kurland said, the new entry requirement only applies to visa-exempt foreign nationals who are flying into or through Canada, but not to those who are driving across the border.

"The legal advice to people being stranded is to get on a plane to an American city and simply drive into Canada."

"That's ludicrous," Kurland said.

French citizens who are permanent residents in Canada have expressed concerns about the new eTA requirement.

"The fact remains that the decision to delay the enforcement of the eTA requirement is up to Canadian authorities," Florence Ferrari, a spokesperson for the French embassy in Ottawa, said in an email to CBC News.

Ferrari said that any measure to ease its coming into effect will be most welcomed.

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