OTTAWA -- An agreement has been reached between Canada and the United States to keep the border closed to all non-essential travel for another month, Prime Minister Justin Trudeau announced Tuesday, calling it the 鈥渞ight thing鈥 to do. He is cautioning that it could be months still before non-essential travel is allowed.

The extension on the existing agreement means that the border restrictions will stay in place until June 21, even as parts of both countries begin gradually reopening. The agreement, as it stands, exempts the flow of trade and commerce, as well as vital health-care workers such as nurses who live and work on opposite sides of the border. Tourists and cross-border visits remain prohibited.

鈥淭his is an important decision that will keep people in both of our countries safe,鈥 Trudeau said on Tuesday. Facing questions about the cross-border decision, Trudeau said there was a clear desire from premiers to keep up the border closure.

鈥淭he decisions that we're taking are very much made week-to-week in this crisis. The situation is changing rapidly and we're adjusting constantly to what are the right measures for Canadians to get that balance right between keeping people safe, and restoring a semblance of normality and economic activity that we all rely on,鈥 said the prime minister.

Speaking about the agreement at the White House, U.S. President Donald Trump said that 鈥渁s things clean up,鈥 in terms of the COVID-19 pandemic, both sides will 鈥渨ant to get back to normal.鈥

鈥淲e鈥檙e very close to Canada,鈥 he said.

To date there have been more than 79,000 COVID-19 cases in Canada, and nearly 6,000 people have died, while the United States currently has more than 1.5 million active COVID-19 cases and more than 90,000 people have died in that country.

Talks had been underway since last week, with Canada wanting to see the travel limitations left in place, despite a growing push from Canadians who want to be reunited with loved ones who live across the border.

The prime minister continues to emphasize that reopening Canada鈥檚 border to international travel would be risky as countries worldwide are still working to contain outbreaks and more robust contact tracing has yet to be established.

鈥淲e will continue to watch carefully what's happening elsewhere in the world, and around us as we make decisions on next steps,鈥 Trudeau said.

In an interview on CTV鈥檚 Power Play, Public Safety Minister Bill Blair said the current agreement is 鈥渨orking well,鈥 and Canada will continue to maintain the ban on non-essential travel 鈥渁s long as it鈥檚 necessary.鈥 

Ahead of the extension being announced, outgoing Conservative Leader Andrew Scheer said the government needs to put in place a clear plan for when a more broad reopening of travel could be possible, how that reopening would be managed and how further risks mitigated.

鈥淲e鈥檝e also heard from individual cases of hardship, for individuals who are separated because of the closure. We certainly have a lot of compassion for those spouses who have been separated, or children who don鈥檛 have access to one parent or another,鈥 Scheer said earlier on Tuesday.  

This is the second time the agreement has been extended, after first being imposed in March, with the current extension on border restrictions set to expire May 21.

14-DAY ISOLATION KEY: TAM 

The prime minister said this extension gives Canada another month to figure out how to answer questions such as what further measures will be required when the border does reopen to ensure that people crossing the border don鈥檛 become vectors for further spread of the deadly respiratory virus in Canada.

He said while planning is already happening on what 鈥渟trong measures鈥 will be imposed, it will become crucial once the time comes for non-essential travel to pick back up, which he estimates will be 鈥渋n the coming months.鈥  

Asked about what the public health argument is for continuing to keep the Canada-U.S. border closed and what the benchmarks will be for signs it鈥檚 an appropriate time to loosen those restrictions, Chief Public Health Officer Dr. Theresa Tam said the first step would be carefully reopening travel restrictions within Canada.

She said drastically limiting who has been able to enter the country over the last two months鈥攏early all international visitors鈥攈as been key to Canada controlling the outbreak.

Canadian health officials will continue to watch the United States鈥 epidemic and trajectory to see whether it will be appropriate come June 21 to lift restrictions or continue to maintain them.

Further, Tam said that even when international travel can resume, the 14-day mandatory quarantine and follow up enforcement of that order will remain 鈥渁 cornerstone鈥 of the disease control measures.

鈥淔undamentally, it's about ensuring that whatever we do, the system is still able to detect and still able to cope with any introduction,鈥 Tam said.