WASHINGTON — It may take three-quarters of Canadians getting vaccinated against COVID-19 before Canada and the United States can seriously consider reopening their shared border, Justin Trudeau suggested Tuesday. 

The prime minister acknowledged that preliminary talks — described as "officials-level" by those familiar with the discussions — are ongoing, but tamped down any expectations that cross-border travel restrictions could be lifted any time soon. 

"We know that there are still real concerns around transmission of the virus, but we will continue to work with our partners and hopefully get to a better place when the time is appropriate," Trudeau told a news conference. 

"We're all eager to get back to normal, but we know that before we get back to normal, cases need to be under control and over 75 per cent of people need to be vaccinated."

Discretionary travel between Canada and the United States has been prohibited since March 2020, when the severity of the coming COVID-19 crisis first made itself evident on North American soil.

That restriction, due to expire Friday, is all but certain to be extended by another 30 days before the end of the week. 

Canada is still not out of the current third wave of COVID-19 and has much more work to do before it's safe for travel to resume, Trudeau said — a stark contrast to the brightening skies south of the border. 

In the U.S., a blistering vaccination pace has prompted public health officials to lift face mask requirements for people who are fully vaccinated.

That has some U.S. lawmakers urging President Joe Biden to get serious about drafting a plan to allow travel to and from Canada to resume in time for the July 4 holiday. 

New York Rep. Brian Higgins wrote to Biden last week urging him to "directly engage" with Trudeau on a plan to reopen the border, including a partial easing of the restrictions before the end of the month.

Others, including Democratic Senate Leader Chuck Schumer, have been making similar calls, echoing the concerns of businesses, property owners and border communities that depend on the ability to move easily between the two countries. 

A consortium of Canadian business leaders wrote a similar letter Monday to Trudeau — a letter that happened to mention the same 75 per cent threshold the prime minister did. 

"By midsummer, if not sooner, some three-quarters of Canadian adults will be at least partially vaccinated, and one in five will be fully vaccinated," by which point restrictions ought to be eased, reads the letter, signed by the presidents of the Canadian Chamber of Commerce and Canadian Manufacturers & Exporters, among dozens of others. 

"As the light at the end of the tunnel grows brighter, Canadians will be looking to their leaders for transparency, guidance and a clear plan."

The White House, for its part, is constantly assessing the situation in other countries to ensure it has the right controls in place, press secretary Jen Psaki said Monday.

But as for whether the U.S. has a target date in mind for opening the border, Psaki was noncommittal. 

"I don't have any update on the timeline," she said. 

"We are certainly always assessing as it relates to travel borders … what we need to do and keep in place in order to keep the American people safe, especially during a global pandemic. But we are constantly evaluating."

This report by The Canadian Press was first published May 18, 2021.

— With files from Jordan Press in Ottawa 

James McCarten, The Canadian Press