An infectious disease expert said on Thursday that a government proposal to substantially raise fines for people who breach anti-epidemic rules is unfair to the poor.

Sources said the government is considering increasing the fine for those who violate social distancing regulations from the current HK$2,000 to HK$10,000.

Dr Leung Chi-chiu said with the wide wealth gap in Hong Kong, those from low-income groups would especially feel the pinch if the fine is set too high.

"Two thousand dollars may not be a small amount for segments of our society with low income, especially for our (foreign) domestic helpers," Leung told RTHK.

"If we increase the amount to a very high level, such that they cannot pay, there may be a question whether we're fair to them, because they would be selectively prosecuted."

Rather than raising fines, Leung said the key is to strengthen law enforcement, with many venue owners flouting the rules once inspection officers leave.

"I think it is important that we, first, enforce the law strictly. If we find at that stage that there is not enough deterrence and people are still gathering unlawfully, in that case I think there may be a better reason to increase the level of the fine."

Meanwhile, home affairs secretary Casper Tsui said government departments will step up law enforcement in the coming weeks.

He also told an RTHK radio programme that he hopes a higher fine would deter people from breaking the rules, rather than officials having to enforce the law.