Japanese Prime Minister Shinzo Abe has said a threat by Islamic State (IS) militants to kill two Japanese hostages is "unforgivable" and demanded their immediate release.
Speaking in a press conference in Jerusalem on January 20, Abe promised that Japan would do its utmost to secure the safe release of Kenji Goto Jogo and Haruna Yukawa, saying that "their lives are the top priority."
A video released online on January 20 purports to show the IS group threatening to kill the two men unless a $200 million ransom is paid within 72 hours.
The video was posted on militant websites associated with IS militants and was similar to previous clips released by the extremist group.
In it, a black-clad figure with a knife criticizes what he says is Japanese support for a U.S.-led coalition conducting a military campaign against IS militants.
The man speaking in the video resembles and sounds like a British-accented militant involved in other beheadings carried out by the Sunni extremist group.
The militant says that the ransom demand is to compensate for nonmilitary aid that Japanese Prime Minister Abe pledged to support countries fighting IS militants during his Middle East tour.
Abe said he would honor his promise of a multimillion-dollar aid package despite the threat by IS militants.
"The international community will not give in to terrorism and we have to make sure that we work together," he said.
Abe pledged a total of $2.5 billion in humanitarian and development aid for the Middle East on the first leg of his tour in Cairo on January 17.
In Tokyo, the Japanese Foreign Ministry said it was checking the video to see whether the footage was genuine.
Cabinet ministers announced that they were meeting to discuss the government's response to the militants' threats.
One hostage, Kenji Goto Jogo, is a freelance journalist.
The other, Haruna Yukawa, appeared in previous footage posted last August in which he was shown being roughly interrogated by his captors.
A Tokyo-based private military firm has listed Yukawa as its chief executive. Its website said the firm has branch offices in "Turkey, Syria, Africa."
Islamic State militants have used hostages a propaganda tool.
They have beheaded and shot dead hundreds of captives, including Syrian and Iraqi soldiers and Western journalists and aid workers.
The groups had released gruesome videos of the beheadings of American hostages James Foley and Steven Sotloff, and British hostages David Haines and Alan Henning among others.
The group also holds British photojournalist John Cantlie, who has appeared in extremist propaganda videos, and a 26-year-old American woman captured in Syria while working for aid groups last year. U.S. officials have asked that the woman not be identified out of fears for her safety.
IS militants hold large parts of northern Syria and Iraq after an offensive last summer.
The United States is leading a coalition targeting the militants with air strikes and helping Iraqi military and Kurdish forces fight them as part of what President Barack Obama has called a multipronged campaign to "degrade and ultimately destroy" the militant group.
A video released following Islamist attacks that killed 17 people in Paris on January 7-9 showed one of the attackers, Amedy Coulibaly, declaring allegiance to the IS militant group.