Russian hackers’ attempts to bring down Canadian government websites will "in no way" dissuade Canada's unwavering support for Ukraine, Prime Minister Justin Trudeau said Tuesday.

"As you know, it's not uncommon for Russian hackers to target countries as they are showing their steadfast support for Ukraine, as they are welcoming Ukrainian delegations or leadership to visit. So, the timing isn't surprising," Trudeau said.

The prime minister—appearing alongside Ukrainian Prime Minister Denys Shmyhal following a bilateral meeting in Toronto—was asked to comment on his prime ministerial website going down for a brief period of time on Tuesday, and whether it was due to Russian hacking. 

"In case anyone was wondering, Russia being able to bring down an official Government of Canada webpage for a few hours, is in no way going to dissuade us from our unshakeable support of Ukraine," Trudeau said.

In a statement to CTV News about Trudeau’s website going down, Privy Council Office spokesperson Pierre-Alain Bujold said the office worked with Shared Services Canada and the Communications Security Establishment’s Canadian Centre for Cyber Security “to investigate and resolve the issue as soon as possible.”

On Monday, a handful of other government websites also failed to load, with a so-called "hactivist" group purporting to be behind what appeared to be potential distributed denial-of-service (DDoS) attacks. 

The Senate of Canada’s website was among those that appeared to have been impacted, with the page unable to load much of the day on Monday. 

With the site back online Tuesday, spokesperson for the Senate Standing Committee on Internal Economy, Budgets and Administration Alison Korn told CTV News that "the incident is being investigated."

Asked for further details on what was behind the lengthy downing of the site, Korn said "details pertaining to the Senate's IT security are confidential for security reasons."

Also experiencing issues Monday was the National Capital Commission site.

The agency's strategic communications senior manager Valerie Dufour told CTV News in a statement that it "noticed a high volume of traffic" and was "investigating the source of the problem" but expected to have the issue resolved soon. The page was up and loading without issue on Tuesday.

On Monday, the Communications Security Establishment (CSE) would not confirm or deny the Russian hacker claims but said it was "aware of reports that some Government of Canada websites have been off line."

"The Government of Canada, like every other government and private sector organization in the world, is subject to ongoing and persistent cyber threats," said CSE spokesperson Ryan Foreman in a statement.

He said that there's cross-department collaboration to ensure "there are systems and tools in place to monitor, detect, and investigate potential threats, and to neutralize threats when they occur."

On any given day, Foreman said that CSE's defensive systems can block between three to five billion events targeting Government of Canada networks.

With files from CTV National News' Kevin Gallagher and Glen McGregor