WASHINGTON -- Despite a summer travel season hamstrung by COVID-19, Canada's border agents are bracing for a spike in would-be travellers trying to enter the country on the first full weekend since travel restrictions began to ease.

The Canada Border Services Agency says incoming traffic has increased about 25 per cent since Monday, when quarantine rules were waived for fully vaccinated Canadians, permanent residents and others already allowed to cross the border.

That trend is likely to continue this weekend, said Denis Vinette, vice-president of the agency's travellers branch.

“We've been seeing kind of this 25 per cent increase over a few days, and it'll be interesting to see what happens on the weekend,” Vinette said.

“We ask people to be patient at the border if they find that there are long lineups and folks coming in for the weekend. It's our first test, if you will, especially in the land border environment.”

Of those seeking entry to Canada under the exemption, about half were turned away, Vinette said - mostly because they weren't fully vaccinated or received a vaccine not cleared for use in Canada.

Only Canadian citizens, permanent residents and eligible foreign nationals who have gone two weeks since a full course of one of the four COVID-19 vaccines approved by Health Canada - Pfizer-BioNTech, Moderna, Oxford-AstraZeneca or Johnson & Johnson - are exempt from quarantine.

Canada has exceptions in place for foreign nationals who are immediate family members of a Canadian citizen or permanent resident, as well as a process to allow extended family members and international students to apply for entry.

Travellers must also use the ArriveCAN app or online portal to submit their vaccine information and the results of a negative COVID-19 test taken no more than three days before departure.

“The big thing for folks to understand is what qualifies as a fully exempted traveller under Canada's definition,” Vinette said in an interview Friday.

“It is about having had one of the four Health Canada vaccines. It's about having had the full regimens, or both shots, and having had 14 days pass after your second shot.”

Air Canada and WestJet are also helping to promote the rules with signage in airports, and airport authorities and provincial public health agencies are also doing their part, Vinette said.

Of those seeking the exemption, about half had either had only one shot, received their second dose less than 14 days before arrival or got a vaccine other than the four that have been approved in Canada, he said.

“I'm not suggesting that people are trying to, you know, squeeze themselves in; it's more a question, I think, of folks not understanding the rules.”

Vinette said the agency is anxious to make sure people understand what has changed and what has not in order to prevent excessive delays or tie-ups at border control points.

He said the delays have not been extensive, except for at busy border crossings like Windsor-Detroit, Fort Erie, Ont., and the Pacific Highway crossing in B.C., where peak wait times were sometimes close to 45 minutes.

“That is still just the early days of verifying,” Vinette said.

“When you see that you've got 50 per cent or thereabouts that maybe don't qualify, we want to make sure we aren't affording the right to be exempt from quarantine to those who don't qualify, especially if it's going to create a risk in our communities.”

The ArriveCAN portal can be accessed either via the Apple or Android app or online via the federal government's website at canada.ca. Travellers must use the latest version of the app, which was updated when the rules changed.

As for when the restrictions will be relaxed further, that remains an open question.

Prime Minister Justin Trudeau said Thursday he has no intention of jeopardizing Canada's recovery from the pandemic by prematurely opening the border. He said the next step would be easing the restrictions on fully vaccinated travellers who aren't Canadian, but didn't say when that might happen.

South of the border, patience continues to run low.

Senate Majority Leader Chuck Schumer, who represents the border state of New York, urged the two countries to come up with a mutual plan to reopen the border as soon as possible - and failing that, for the U.S. to take unilateral action.

“If an agreement cannot be reached … the United States must do two things: expand the definition of essential travel to include vaccinated Canadian citizens with family, property, educational, medical, or business interests (in the U.S.), and unilaterally open the northern border to those vaccinated Canadians,” Schumer said in a statement this week.

“For over a year, we have been told to follow the science, facts, and data; it's time for the U.S. to do the same and finally take the first move in good faith to safely reopen the border to vaccinated Canadians.”