Canadian Prime Minister Justin Trudeau said he was outraged by the death of Canadian hostage John Ridsdel in the Philippines, calling it an act of "cold-blooded murder."
The former mining executive was executed by Abu Sayyaf militants in the Philippines, the Canadian government confirmed earlier.
Mr Ridsdel was abducted in September last year.
Mr Trudeau said efforts were continuing to secure the release of a second Canadian still being held along with a Norwegian and a Filipina.
Mr Ridsdel, 68, was captured by Islamist militants along with the three other people while on holiday on Samal Island.
"Canada condemns without reservation the brutality of the hostage-takers and this unnecessary death. This was an act of cold-blooded murder and responsibility rests squarely with the terrorist group who took him hostage," Mr Trudeau told reporters on the sidelines of a cabinet meeting.
"The government of Canada is committed to working with the government of the Philippines and international partners to pursue those responsible for this heinous act."
We are outraged by the cold-blooded murder of Canadian John Ridsdel at the hands of terrorists. Full statement: https://t.co/2ZKpScKN7F
— Justin Trudeau (@JustinTrudeau) April 25, 2016
Mr Trudeau declined to respond when asked whether the Canadian government had tried to negotiate with the captors or pay a ransom, or whether it was trying to secure the release of the other Canadian being held, Robert Hall.
A Philippine army spokesman said al Qaeda-linked Abu Sayyaf militants had threatened to behead one of four captives today if the 300 million pesos ($6.4 million) ransom for each of them was not paid by 3pm local time.
The initial demand was one billion pesos each for the hostages.
Abu Sayyaf is a small but brutal militant group known for beheading, kidnapping, bombing and extortion in the south of the country.
It decapitated a hostage from Malaysia in November last year on the same day that country's prime minister arrived in Manila for an international summit. Philippine President Benigno Aquino ordered troops to intensify action against the militants.
Security is precarious in the southern Philippines, despite a 2014 peace pact between the government and the largest Muslim rebel group that ended 45 years of conflict.
Abu Sayyaf is also holding other foreigners, including one from the Netherlands, one from Japan, four Malaysians and 14 Indonesian tugboat crew.
