As more of the world's population move to urban areas, it will be mayors and city governments - rather than national ones - that find themselves on the front line of battles on issues such as inequality and climate change.
The changing role of mayors took centrestage on the first day of the World Cities Summit Mayors Forum in New York as speakers continually stressed the responsibility that city leaders face.
During his welcome address, New York Mayor Bill de Blasio told his fellow mayors that, unlike national governments, local leaders did not have the luxury of simply debating issues.
"Every day, the issues visit us upon our doorstep. Every day, the issues are present in the lives of our people and are urgent to us. And that is why it is a special honour for me to be your colleague, because that urgency represents the highest form of public service in my view. We, by definition, are the actors and the doers, and we innovate, and we create because we know we must," he said.
Mr De Blasio added: "The reality of governance is changing because the pertinence of cities is greater with every passing year, and we are, in fact, the spark of change. We are the centre, the focal point, more than ever before in history."
The mayors forum, organised jointly by Singapore's Centre for Liveable Cities and Urban Development Authority, brings together local government leaders from about 70 cities around the world. This year's meeting is only the second time the summit is being held outside of Singapore.
The growing importance of mayors was also a theme in the speeches of Minister of State for National Development Desmond Lee and United Nations Deputy Secretary-General Jan Eliasson.
Mr Lee, the forum chairman, warned city leaders of the need to be flexible, given how rapidly the nature of challenges is changing, saying: "Urbanisation, globalisation and the explosion of the information age are increasingly intertwined. The confluence of these three forces has had, and will continue to have, a tremendous impact on societies around the world. As city leaders, we need to be prepared, be flexible and adaptive enough to capitalise on these forces to benefit our people."
Mr Eliasson, in turn, paid tribute to the good work being done at the city government level.
"For me sometimes, in the UN, where we deal with lofty ideas on the global level, it is very good to be reminded of things being done on the ground, in the field. I've always encouraged seeing the entrepreneurship and innovative spirit characterised by mayors around the world," he said.
Over the course of the two-day summit, mayors will share with one another the various initiatives that have worked for their cities. Singapore's planners will be making various presentations and also hoping to glean some ideas that could be implemented back home.
Mr Khoo Teng Chye, executive director of the Centre for Liveable Cities, told the Singapore media on Tuesday that what he has seen in New York could help inform some Singapore projects. He noted, for instance, the parallels between the successful New York High Line - an abandoned railway turned into a 2.3km park - and Singapore's rail corridor.
He said: "We have to be careful not to copy things precisely, but we have a rail corridor. Our rail corridor is much longer - it is 24km - and I think the High Line offers us some lessons of what we can do to learn from their very successful experience."
This article was first published on June 11, 2015.
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