MANILA: Islamist militants operating along the Philippines' porous southern borders with Malaysia have released a new video threatening to kill an elderly German hostage on Feb 26 if they are not paid 30 million pesos (RM2.6mil) in ransom.

In the video released on Tuesday via the chat app Telegram, Juerguen Kantner, 70, can be seen speaking in German, apparently pleading for his life.

A caption in the video said this was a "final ultimatum" from the militants holding Kantner, who was abducted last year.

"If their demand of 30 million pesos is not met by Feb 26, at 3pm, they will behead the hostage and post it on social media," it read.

Kantner was abducted by Abu Sayyaf militants while he and his wife Sabine Merz were cruising a dangerous area of the Philippines last year. His wife was killed, purportedly when she tried to fight back with a shotgun.

The couple had been sailing the oceans for many years aboard their 53-footer, the Rockall. They were held for 52 days in Somalia in 2008 before their captors freed them, reportedly after a six-figure ransom had been paid.

The Abu Sayyaf, an insurgent group known for kidnapping foreigners for ransom, has defied more than a decade of US-backed military offensives against it and has conducted a lucrative kidnapping spree in recent years.

In 2014, the militants abducted another German couple off a yacht in the southern Philippines. They released the pair six months later after receiving what they said was the full ransom demand of US$5.1mil (RM22.68). - The Straits Times/Asia News Network