Kuala Lumpur. Governments overseeing Asia's rapidly-expanding cities must give young people greater opportunities in order to avoid unrest like the Arab Spring, said the regional head of the United Nations development agency.
In an interview in Kuala Lumpur, Haoliang Xu cited the Arab Spring protests, which convulsed North Africa and the Middle East in 2011, as a movement that began with young people's disillusionment about the future.
"Inequality breeds instability," said Xu, director for Asia-Pacific at the United Nations Development Programme (UNDP). "It is a really critical issue. The risks are there."
Cities in the Asia-Pacific region have seen unprecedented growth over the last two decades.
This year, more than half the region's population will for the first time be urban, and that figure will rise to two-thirds by 2050, the UNDP estimates.
"If nothing happens you will have more polarization of societies," Xu told the Thomson Reuters Foundation.
"I'm sure at some point there is a tipping point where things will go from bad to worse, but I see a lot of positive signs," he said on the sidelines of the World Urban Forum, which is the largest conference on sustainable cities.
About 1.5 billion people in the region still lack basic sanitation services, while 250 million people live in slums.
Infrastructure and services in many Asia-Pacific cities have struggled to keep pace with rising populations and economic growth, while the affects of climate change have created further challenges.
But rather than focus solely on raising incomes to solve inequality, Xu said young people must be allowed to participate in the decisions that shape the cities where they live in.
Governments embarking on major infrastructure projects -- like transport -- should involve young people and future users during the planning stages, said Xu.
"If you empower the young people today, you empower them in the future," he said.
The 17 Sustainable Development Goals (SDGs) approved by 193 UN member states in 2015 to conquer poverty, climate change and other issues could be used to address inequalities and hold governments to account, he said.
Businesses can also promote sustainability - and doing so may also encourage customer loyalty.
Governments can play a key role in convincing small and medium-sized businesses to engage with communities, and should provide fiscal incentives to stimulate investments in innovative technologies, said Xu.
"You encourage companies to invest in technology that will produce a positive return for the environment," he added.