BUSAN - The upcoming expansion to Changi Airport will be built on a higher level of reclaimed land to protect against rising sea levels, said Prime Minister Lee Hsien Loong on the sidelines of the Asean-Republic of Korea Commemorative Summit in Busan.

Noting that Singapore has been raising its standards for reclamation and new buildings to ensure a higher ground level, he encouraged Asean and South Korea to also work more closely together in tackling climate change and other "non-traditional security issues" such as infectious diseases and terrorism.

Such issues pose a serious challenge to Asia and the world, Mr Lee said on Friday.

The 10 Asean nations and South Korea should consider working more closely together to combat challenges such as climate change, diseases, natural disasters and terrorism, he added.

"This will help to ensure a stable and peaceful region that continues to prosper for the benefit of our people," he said.

Speaking in Busan at the Asean-Republic of Korea Commemorative Summit to celebrate 25 years of relations between the 10 Asean nations and South Korea, Mr Lee said a concerted global response was needed to tackle these "non-traditional security issues".

He flagged in particular the rise of sea levels, which he said poses an immediate threat to coastal populations in Asean countries. Sea levels are rising as global warming causes polar ice caps to melt.

Singapore, as a low-lying island state, "takes climate change seriously" and will do its part to manage carbon emissions, Mr Lee added.

He also said Asean and South Korea can cooperate to help move negotiations at the United Nations climate change conference in Paris next year, when 196 countries will meet to sign a global agreement.

Asean countries can also learn from the experience of South Korea, which has implemented a "low-carbon green growth" policy and successfully developed environmentally-friendly technology, Mr Lee said.