The Paris Agreement to curb global climate change must now pivot from diplomacy to implementation, said top officials gathered at the UN headquarters where 175 nations signed the landmark accord, making it the biggest one-day endorsement of a global deal.
The accord is a "strong affirmation that diplomacy is essential and capable of solving problems on the global commons", said Minister for Foreign Affairs Vivian Balakrishnan at the ceremony on Friday.
But he emphasised the importance of turning words into action and building on the momentum from the Paris meeting of last year.
"We all need to remember that we have to take decisive pre-2020 actions in order to create a solid foundation for our post-2020 commitments," Dr Balakrishnan said.
The deal reached in December commits states to hold global warming to well below 2 deg C.
WALKING THE TALK
We have proven that an agreement can be built on a spirit of cooperation and collaboration. And that there is a pathway to raise ambition, to enhance global support for climate action, and to improve over time.
DR VIVIAN BALAKRISHNAN, Minister for Foreign Affairs
While there are hopes that the deal can be brought into force before the initial target date of 2020, many states still require a parliamentary vote to formally approve the accord.
Taking the lead on this issue were China and the United States - the world's top greenhouse gas producers - which pledged to adopt the accord by the end of the year.
"The urgency of this challenge is only becoming more pronounced... The United States looks forward to formally joining this agreement this year and we call on all of our international partners to do so," said US Secretary of State John Kerry, reminding the audience at the United Nations that 2015 was the hottest year on record and last month was the hottest-ever-recorded March.
The Paris accord will enter into force only when ratified by at least 55 nations representing 55 per cent of man-made greenhouse gas emissions.
Together, China and the US account for 38 per cent of these emissions.
"China will finalise domestic legal procedures on its accession before the G-20 Hangzhou summit in September this year," said Chinese Vice-Premier Zhang Gaoli at the UN signing ceremony.
Domestically, early actions have already allowed Singapore to achieve relatively low carbon emissions per GDP dollar, said Dr Balakrishnan, but more can be done.
He said Singapore will pursue renewable energy in the form of increased solar photovoltaic deployment.
"This will supplement our substantial energy efficiency efforts and other mitigation measures to lower our emissions intensity by 36 per cent from 2005 levels, and to stabilise our emissions around 2030," he said.
Dr Balakrishnan acknowledged that "difficult conversations" had transpired to make the agreement happen, but added that the accord has shown there are ways for countries to work together for a "balanced and inclusive outcome".
"We have proven that an agreement can be built on a spirit of cooperation and collaboration. And that there is a pathway to raise ambition, to enhance global support for climate action, and to improve over time," he said.
In encouraging countries to continue to work together, Mr Kerry said: "The new energy future, the efficiencies, the alternative resources, the clean options - none of what we have to achieve is beyond our capacity technologically.
"The only question is whether it is beyond our collective resolve."