Beijing is not what it used to be. Its population has tripled since half a century ago.

Population explosion is not just a global issue, but one that Beijing policy-makers and local citizens have to tackle.

Currently, Beijing has about 15 million residents, with 3 million being the so-called "migrant population," or those without local permanent residence.

Meanwhile, Beijing is troubled by serious pollution, overcrowding, traffic jams and energy shortages, among other challenges.

Naturally, some locals readily link all these with the inflow of non-Beijing residents and advocate ways to block off people from other regions to ease the city's tensions.

The latest call comes from a Beijing demographer, who has proposed raising property prices for non-Beijing buyers.

Similar proposals have been made in the recent past. A government policy adviser suggested early this year that an access card system for labourers from other parts of the country entering the capital be implemented.

Both proposals reflect concern about Beijing's living environment. While this is understandable, restrictive measures will infringe upon people's right to migrate.

Beijing has used measures to restrict the entry of outsiders in the past.

In the 1980s, the city once levied special fees on people from other regions moving to the city. By 2000, people without a Beijing permanent residence were not allowed to purchase commercial property.

These regulations have been scrapped now. And it is much easier for outsiders to apply for temporary local residence to stay in the capital.

The policy changes have made Beijing more open.

But we should know that the abandonment of the policies is not an act of kindness. It is because they go against the times and violate people's rights.

In the same vein, the latest suggestions to restrict mobility, no matter in what lofty language they are couched, are unacceptable.

Policy-makers should not try to resort to the easiest way to run a city, but look for one that respects people's rights. More effort towards this end is worth expending.

We should not, of course, ignore the problem Beijing's overcrowding poses. But we are not at our wits' end to find a better solution.

The root cause of the problem is the regional imbalance between Beijing and other cities. Beijing can provide, at least, more jobs than other cities.

On the other hand, Beijing has enjoyed a fiscal preference from the national public coffer. It accommodates about 1 per cent of the nation's population, but is estimated to gulp up to 2.7 per cent of the national fiscal allocations.

It is thus more advisable to reconsider our fiscal allocation regime and earmark more fiscal resources for the development of cities other than such national hubs as Beijing and Shanghai.

The cross-city transport networks need to be updated and local infrastructure improved to usher in more investment in the small and medium-sized cities so that their economies can prosper and attract more labour.

The government can devise preferential policies to encourage people to move to small and medium-sized cities.

If effectively implemented, a more balanced development strategy would deflect some of the population headed to the big cities and ease population pressures in cities such as Beijing before the problem spirals out of control.

China's employment in the tertiary industry remains low. It is expected to rise sharply as the society develops. This means the labour movement to the big cities is yet to peak.

Blocking this movement would mean a violation of the rights of migrant labour. Beijing and other Chinese metropolises need to rack their brains to work out better solutions.