William arrived at Jewel, a nature-themed complex at Changi Airport, for an event welcoming him on Sunday at 5.30pm local time (9.30am GMT) after he took a 13-hour commercial flight from the UK.
The prince, wearing a dark navy suit, was met with cheers from hundreds of people waiting below as he appeared on a balcony with Sim Ann, Singapore’s senior minister of state for foreign affairs and senior minister of state for national development, at the HSBC Rain Vortex, the world’s largest and tallest indoor waterfall.
He then spent time meeting Singaporeans during a walkabout at the Shiseido Forest Valley, the indoor garden located in Jewel, who gave him gifts, shook his hand and posed for selfies.
The prince even affectionately allowed an eight-month-old baby to suck on his finger.
The family with the baby, named Albane Costa, were on a three-day layover in Singapore from New Caledonia to France to visit father Ervan’s parents.
Speaking ahead of William’s arrival, Amna Yaacob, who was waiting in the crowd, said: “I’m so excited and shocked, I had no idea Prince William was coming.”
She added: “This is the one chance I will get in my life, it’s a dream.”
The prince said Singapore’s “bold vision to be a leader for environmental innovation sets the standard for others to follow”.
He added: “I am grateful to the Singaporean people for hosting us this week.
“Let us all take inspiration from the fantastic work being done here as we celebrate this year’s Earthshot Prize finalists.”
A Tembusu tree was also planted to commemorate the visit, which was chosen as a well-known native plant to Singapore, which features on its five dollar note.
It was also chosen in recognition of the Tembusu sapling the late Queen planted at Jurong Hill during her visit to Singapore in 1972.
It marks the first time a foreign or local dignitary has ever planted a tree at Changi Jewel.
The prince was shown the tree by the chief executive of Jewel, James Fong.
The awards, which are aimed at recognising solutions to “repair” the planet, will see five category winners presented with £1 million each to scale up their environmental ideas.
Robert Irwin, son of the late Australian wildlife conservationist Steve Irwin, will join a host of stars including Oscar winner Cate Blanchett, producer Donnie Yen and actors Lana Condor and Nomzamo Mbatha announcing the winners at the ceremony on Tuesday.
Hosting the event will be Hannah Waddingham, who performed similar duties when Liverpool staged the Eurovision Song Contest earlier this year, and Emmy Award-winning actor and producer Sterling K Brown.
Performers will include Bebe Rexha, Bastille and OneRepublic, and Earthshot Prize Council member Sir David Attenborough will make a video appearance during the broadcast.
William held his first Earthshot Prize awards ceremony at London’s Alexandra Palace in 2021, with Boston hosting the event last year.
Among the 15 finalists are Enso, a British-based company which has created a more efficient electric vehicle tyre that sheds less particles, while Sea Forest from Australia has developed a seaweed-based livestock feed to reduce the planet-warming methane emissions from cattle and sheep.
During his four-day trip to Singapore, the prince will take part in Earthshot Week, a series of events bringing together businesses and investors with past winners and current finalists to accelerate their solutions.
William will take part in dragon boating, meet Singaporeans to learn how they are working locally to protect the planet, while the 15 finalists will take part in a “fellowship” retreat that will give them networking opportunities.
The prince will also attend a United for Wildlife summit, aimed at tackling the illegal trade in animal parts.
This is William’s first visit to Singapore since 2012 when he came to the country as part of a tour of South East Asia and the South Pacific with the then-duchess of Cambridge.