The issue of whether Singapore should one day consider dual citizenship has been raised from time to time in discussions about the future of Singapore citizenship.

For example, parliamentary questions last year and in 2013 quizzed the Government on its position.

The Government's reply: As Singapore is a "small and young nation", dual citizenship could dilute citizens' commitment to the country.

But Ambassador Barry Desker of the S. Rajaratnam School of International Studies, a prominent advocate of dual citizenship, argues that it helps root two groups to Singapore: first, Singaporeans living abroad and, second, foreigners in Singapore who are married to Singaporeans.

Singapore "may be losing good people" when Singaporeans living abroad are forced to give up their citizenship, says Professor Tan Tai Yong of Yale-NUS College.

Associate Professor Eugene Tan of Singapore Management University says: "I would say, 'never say never'... However, it should be a means of last resort, when Singapore is confident that dual citizenship will not have a detrimental impact in terms of people's sense of belonging to the country."

A strong opponent of dual citizenship is Professor Leo Suryadinata of the ISEAS-Yusof Ishak Institute.

He argues that citizenship is about political loyalty and it is doubtful if a person can be loyal to two countries. He adds that in an age of growing nationalism and the potential break-up of the European Union, global trends appear to be moving away from dual citizenship.

Institute of Policy Studies researcher Debbie Soon says if Singapore were to one day be in conflict with another country, dual citizenship would be problematic because of Singapore's conscription system. Singapore also lacks a religious or cultural heritage to help it call on the loyalties of such dual citizens, which some countries with a longer history may have, she notes.

But discussions on dual citizenship do not have to yield a binary yes-or-no answer, argues Associate Professor Elaine Ho of the National University of Singapore.

There are in-between options that may enhance the links people have to Singapore, she notes.

One is the British example of an ancestry visa, which offers foreigners who can prove ancestral links to Britain an inside track to living and working there. A similar concept is the Overseas Citizenship of India.

Prof Tan Tai Yong notes that the honorary citizenship, which Singapore grants to a very select group of foreigners who have made outstanding contributions to the country, is also an example of an in-between option.

Elgin Toh