The Federation of Hong Kong and Kowloon Labour Unions on Tuesday urged the government to review the city's minimum wage annually, instead of once every two years.

It also said the planned rise next month, from HK$37.5 per hour to HK$40, isn't enough, and the wage should be set at HK$46.

The federation said a recent survey it carried out involving 390 people found 70 percent backed the idea of a review every year.

The group's Lam Chun-sing said the government should take reference from the Comprehensive Social Security Assistance (CSSA) scheme.

"The two-person amount (for CSSA) plus the additional rent allowance is about HK$9,000 (per month). If a worker works eight hours per day and 26 days a month, then the hourly wage is around HK$46," he said.

The federation's secretary-general, Chau Siu-chung, added that they would be open-minded as to whether the government should establish a formula to calculate the minimum wage – as long as it doesn't go down.

On Sunday, the Society for Community Organisation urged the government to raise the minimum wage to HK$53.4 per hour.