No problem can be solved by acting alone in a globalised world, Ambassador-at-large Tommy Koh said on Monday, addressing over 50 students from around the world at a summit at Raffles Institution.

He added that the youth today is a "fortunate generation" in a world where they are free to cross borders to pursue their dreams, but as "global citizens" they have a responsibility to the world.

Prof Koh was leading a panel of four ambassadors to Singapore. They are South Africa's Hazel Ngubeni, the Philippines' Minda Calaguian Cruz, France's Olivier Caron and Norway's Tormod C. Endresen. The speakers took turns to share their views on four topics - healthcare, environment, poverty and migration.

Over the next five days, the students will work in groups of 12-15 with local non-governmental organisations (NGOs) to tackle social problems. They will come up with solutions and present their findings to the NGOs at the end of the summit.

Organised by Raffles Institution, the five-day event, known as the Tiltshift Summit, brings together students from 25 schools from countries like the United States and Pakistan. The summit was first held in 2011.