Canadian Prime Minister Justin Trudeau said on Tuesday that attempts by Russian hackers to take down Canadian government sites "will not in any way deter" Canada's steadfast support for Ukraine.

In this context, the Prime Minister – who appeared alongside Ukrainian Prime Minister Denys Shmyhal after a bilateral meeting in Toronto – was asked to comment on the brief hacking of his official Prime Minister's website on Tuesday, and whether it was due to Russian hacking.

Trudeau said: "For anyone wondering, Russia's ability to take down an official Canadian government webpage for a few hours will not in any way deter our steadfast support for Ukraine."

Also, in a statement to CTV News regarding the Trudeau site disruption, a spokesperson for the Privy Council Office, Pierre-Alain Pougault, said the office has been working with Shared Services Canada and the Canadian Centre for Cyber Security within the Communications Security Establishment "to investigate the issue and resolve it as soon as possible."

The Canadian Senate website was also among the government sites that appeared to be affected, as the page failed to load for most of Monday.

With the site back up today, Alison Korn, spokesperson for the Senate Standing Committee on Internal Economy, Budgets and Administration, told CTV News that "the incident is under investigation."

When asked for more details about why the site was hacked, Korn said, "Details related to the Senate’s IT security are confidential for security reasons."

Meanwhile, the National Capital Commission website also faced problems on Monday.

On Monday, the Communications Security Establishment (CSE) neither confirmed nor denied claims by Russian hackers that they were behind the hacks but said it was "aware of reports that some Canadian government websites were offline."

CSE spokesperson Ryan Foreman said in a statement: "The Government of Canada, like any other government or private institution in the world, is subject to ongoing cyber threats."

He added that there is cooperation between departments to ensure "there are systems to monitor, detect, investigate potential threats, and neutralize threats when they occur."