The Philippines will allow Malaysian and Indonesian maritime forces to pursue Islamist kidnappers into its waters, Malaysian Prime Minister Najib Razak said following talks with his counterpart from Manila.
Najib made the announcement after a meeting with visiting President Rodrigo Duterte that focused on recurring kidnappings at sea by Philippine-based Islamic militants.
Najib said Duterte had already agreed the measure with Indonesian President Joko Widodo, or "Jokowi."
"The hot pursuit is a new development. This has been agreed by Duterte and Jokowi, and now with us," Najib said at a press conference in the Malaysian administrative capital Putrajaya.
The waters between Malaysia's eastern Sabah state and the southern Philippines have for years seen repeated kidnappings by the Abu Sayyaf militant group.
"We need to stamp out the kidnap-for-ransom groups. It is affecting us, Sabahans and foreigners who visit us," Najib said.
"We have to continue to pursue and interdict them."
The Abu Sayyaf, a loose network of militants based on remote islands in the southern Philippines, has defied more than a decade of military offensives and been on a lucrative kidnapping spree in recent years.
In the latest reported incident, the Philippine military on Monday said the group had killed a German woman and abducted her companion from their yacht off the southern Philippines.
The two-day trip is the first official visit to Malaysia by the tough-talking Duterte, 71, who did not appear at the press conference.
Elected in May, Duterte has launched an unprecedented war on drugs that has left more than 4,000 people dead.
He said before arriving in Malaysia that maritime security and the fight against piracy were his top agenda items for the trip.
The three countries agreed earlier this year to increase cooperation, including possible joint sea patrols.
While the Abu Sayyaf's leaders have in recent years pledged allegiance to the Islamic State group, analysts say it is mainly focused on running a kidnapping business rather than religious ideology.