Philippines Peace Secretary Jesus Dureza has appealed to Abu Sayyaf to release German hostage Jürgen Kantner after it emerged that the militant group has threatened to behead him if they are not paid 30m pesos (£482,000; $600,000) as ransom by 26 February.

In a latest video released by Site Intelligence Group, Kantner is seen informing his family and the German government about the militants' threat.

The Islamic State (Isis)-linked terror group had killed Kantner's wife – Sabine Merz – and took him hostage from their yacht, in early November 2016 off Laparan Island in Pangutaran, Sulu. His wife's naked body was recovered from the yacht.

The two-minute video reportedly shows Kantner wearing an orange shirt and sporting a beard – in a look that resembles other Abu Sayyaf hostages whose execution videos were released in 2016.

Dureza told Inquirer on Thursday (16 February) that the Filipino government was firm and would not pay any ransom to the militants, but urged them "to spare the life of the victim". He also said that the government would not intervene if the victim's family or any other party wanted to pay for his release.

"The government still reiterates its very strong no ransom policy. So we are not going to talk with them about ransom.

"If someone from the family will pay the ransom for his freedom, we will not intervene because that's personal and they wanted to get him alive," Dureza said.

The minister reiterated that the government was continuing military operations in Sulu to secure the release of Kantner and 19 other hostages.

Philippines President Rodrigo Duterte had ordered his military to annihilate the militant group that has pledged allegiance to IS (Daesh). Recently, the president had warned rogue police officers that they would be sent to Sulu to fight against the dreaded terrorists.

Abu Sayyaf is known for kidnapping and killing innocent people for ransom. The group was highly criticised when it had executed two Canadian hostages in 2016 after the Canadian government refused to pay ransom.