China should gradually increase the retirement age to 65 over the next 10 to 20 years for all workers, top social insurance experts have urged.

The average age of retirement in China is now about 53, while life expectancy is 75, said Wang Dewen, a social protection economist with the World Bank's Beijing office.

The gap is much wider than the 12 years he believes is a reasonable period for an individual to draw a pension.