Turnbull warns terrorist threat growing

Prime Minister Malcolm Turnbull has stressed the need for a "decisive" regional response to terrorism, saying the threat is worsening.

Mr Turnbull and his wife Lucy began their visit to Singapore on Friday with a visit to Kranji war cemetery where World War II allied forces are buried, followed by a trip to the botanic gardens where a yellow orchid was named in their honour.

It comes ahead of a keynote address at a security summit, where he will discuss the growing threat of terrorism in the region and the need for a rules-based order, particularly around issues like the hotly contested South China Sea.

"The threat of Islamist terrorism gets worse in our region," Mr Turnbull told reporters.

Referring to the ongoing battle in the southern city of Marawi in the Philippines between IS-linked terrorists and government forces, Mr Turnbull said the threat of returning foreign fighters was a "very real one" in the region.

"Our response must be as decisive, emphatic and global as the threat that is presented to us."

Australia would continue to support the Philippines through intelligence sharing, he said.