NEW YORK - Singapore is ranked the most religiously diverse country in the world, but its harmonious society did not come about by chance, said Prime Minister Lee Hsien Loong on Monday (Sept 23).

Rather, it worked hard to lay the foundation for religious harmony and then maintain it over the years, he said in a speech when accepting an award from an interfaith group that promotes mutual acceptance and respect.

"We did not become so because Singaporeans are a uniquely virtuous people," said PM Lee, who is on a working visit to New York until Friday.

"We created structures - constitutional, political, social - that discouraged intolerance, curbed chauvinism, and nudged social behaviour in positive ways, long before nudging became intellectually fashionable."

As examples, he cited the state's "strictly secular, but not anti-religious" constitutional approach that treats all faiths impartially, as well as electoral rules to boost multiracial politics, and policies to encourage people of different races to live and study together.

The World Statesman Award is given by the Appeal of Conscience Foundation, a New York-based interfaith group.

Past world leaders who have received the award include former British prime minister David Cameron and former Indonesian president Susilo Bambang Yudhoyono.

Former United States secretary of state Henry Kissinger, 96, read the citation. PM Lee called Dr Kissinger a great and long-time friend of Singapore and a close friend of his father, founding prime minister Lee Kuan Yew.

Dr Kissinger traced Singapore's success as an extraordinarily modern country despite being a small island surrounded by large countries, describing its population as one that has faith in itself.

"I've had the good fortune of knowing the (Lee) family for most of my public life and I've always believed in their contributions to peace and stability in Asia," said Dr Kissinger.

PM Lee said he accepted the award on behalf of all who contributed towards building a harmonious society in Singapore.

But the world is changing, said PM Lee in a 25-minute speech, and Singaporeans must adapt to new forces.

He listed four: growing religiosity among all faiths, external influences, provocative views that proliferate on social media, and violence in the name of race and religion.

First, people among all faiths are taking their faiths more seriously and practising them more fervently, which is not in itself a bad thing, he said.

"But as convinced as one might be of one's own faith, we cannot get carried away, and show disrespect to other people's faiths or other people's gods," he said.

This is why Singapore strongly opposes exclusionary practices that discourage people of different faiths from interacting with one another as fellow citizens, he added.

Such practices include not befriending people of different faiths, or not exchanging greetings with them on one another's religious festivals.

Second, every racial and religious group in Singapore has extensive links with larger communities of the same faith or race abroad, which can mean inadvertently importing disputes and troubles from other lands that can undermine social cohesion.

Singapore, therefore, bans or expels foreign preachers who bring their foreign quarrels to Singapore, or who want to persuade Singaporeans to practise their religions in ways inappropriate for local society, said PM Lee.

"At the same time, we explain to Singaporeans that different societies often practise the same religion in different ways, and we try to inculcate in ourselves confidence and pride in our own practices and norms."

Third, social media means a single offensive or thoughtless post can go viral and be seen by millions in a few hours.

"It has become dangerously easy for people both to cause offence and to take umbrage. We must not allow those who spread toxic views and poison on the Internet to get away with what may literally be murder," said PM Lee, adding that policing the Internet was a Sisyphean task that nevertheless needed to be done.

This was the thinking behind the newly passed Protection from Online Falsehoods and Manipulation Act, which allows the Government and the courts to compel the correction of misinformation and falsehoods online and take action against those who deliberately spread untruths, he said.

Fourth is the continuing threat of terrorists who pervert and misuse religion to justify violence.

PM Lee cited how Singapore thwarted a jihadist attack just after the Sept 11 attacks in 2001, and immediately strove to reinforce trust and confidence between religions.

Muslim leaders came out to condemn the terrorists, while non-Muslim leaders in turn expressed understanding and continued confidence in their Muslim brethren, he said.

Government actions alone cannot bring about religious harmony, said PM Lee, calling on "responsible voices" to spread the message of tolerance and respect.

"I hope future generations of Singaporeans will cherish this harmony, realise how precious it is, and strengthen it further. We must never allow religion to be weaponised, or used as a front for other conflicts," he said.