Canada's terrorism threat level remains at medium in the wake of attacks that killed one Canadian visiting the U.K., but police and security agencies will be on high alert to protect revellers during 150th anniversary celebrations across the country.

Public Safety Minister Ralph Goodale promised "seamless collaboration" between police agencies at the municipal, provincial and federal levels to safeguard Canadians at large and important events. The terror threat level remains at medium, where it has been since fall 2014, he said.

"There is no information available at this time to Canadian authorities that would cause that level to change," he said. "At the same time, it is always under review. Our authorities and agencies are always alert to every bit of information that needs to be taken into account to make sure that threat assessment is as accurate as it can possibly be."

Canadian Christine Archibald was among seven people killed when three people in a van mowed down pedestrians on London Bridge and stabbing bystanders with knives around a nearby market. Of the 48 injured, 21 were in a critical condition.

Goodale says terror threat level unchanged2:16

Goodale extended condolences to Archibald's fiance, family and friends, calling it a sad and traumatic event. But he said Canada would not be deterred by the random attacks as the country gears up to celebrate the nation's sesquicentennial anniversary of confederation.

'We will not be intimidated'

"We will not be intimidated by the horrible behaviour that has been exhibited so recently in the United Kingdom," he said.

This afternoon, MPs rose in the House of Commons for a minute's silence in honour of Archibald and the other victims of the attacks.

Prime Minister Justin Trudeau spoke with U.K. Prime Minister Theresa May earlier in the day, offering Canada's condolences and support.

"We stand in solidarity with the British people," he said during the daily question period.

Trudeau responds to question about London attacks1:14

Trudeau was responding to Conservative Leader Andrew Scheer, in what was his first question to Trudeau since winning his party's leadership.

'We're resilient'

Earlier today, Trudeau said keeping a country safe is the biggest responsibility for any leader.

"Whether it's investing in safety, security, police officers and investigative national security stuff, or whether it's creating a society in which we're there for each other, we lean on each other, we're resilient enough to handle, you know, bad things happening without falling into a bad space," he said during an appearance on Live With Kelly and Ryan, which was broadcasting from Niagara Falls, Ont.

"That balance, defending our security and keeping us Canadian is what people expect of me, and I'm always going to do both of those things."

Member of Parliament remember victims of London attacks3:44