PUTRAJAYA, April 18 — Putrajaya has requested Singapore to be an observer in the patrolling of the Sulu Sea amid several kidnappings by militants from southern Philippines, Defence Minister Datuk Seri Hishammuddin Hussein said today.

Hishammuddin said his meeting with his Singaporean counterpart had gone well and expressed hopes for Malaysia and Singapore, together with other neighbouring countries, to work together for this purpose.

"It is not a new thing for Singapore and Malaysia to work together as we do conduct joint patrolling along the Straits of Malacca.

"It would be good if Singapore can join us as an observer together with Thailand so they can help give us, the Philippines, Brunei and Indonesia, input on how best to tackle the problem," he told reporters at the launch of the 15th Defence Services Asia Exhibition and Conference here.

Hishammuddin recently said that the initiative between Malaysia, Brunei, Indonesia and the Philippines, to ensure safety in the Sulu Sea in the southwestern region of the Philippines must be implemented quickly, after four Indonesians were believed to be kidnapped by armed militants last Friday.

Four Malaysians — Wong Teck Kang, 31, Wong Hung Sing, 34, Wong Teck Chii, 29, and Johnny Lau Jung Hien, 21, all from Sarawak — were previously abducted by Abu Sayyaf-linked gunmen in international waters off Sabah's Pulau Ligitan on April 1.

Despite tight security in Sabah waters, the Abu Sayyaf militant group has staged three kidnappings.