HONG KONG -- A soon-to-be grandfather has filed a lawsuit over a Hong Kong government policy that charges women from mainland China much-higher maternity fees, saying Tuesday it was discriminatory.

Expectant mothers from the mainland -- even those living in Hong Kong -- must pay HK$39,000 (US$5,014; £á3,374) for a three-day stay in a public hospital. Local women pay just HK$100 (US$13; £á8.70) a day.

Hong Kong resident Fok Siu-wing, 65, said the policy discriminates against mainland women like his daughter-in-law, who marry local men and live in the territory. He said he filed a lawsuit against Hospital Authority chairman Anthony Wu on Monday to call for a review.

"The baby is a Hong Kong resident as long as it is born to a Hong Kong resident, so why should we pay a higher fee?" Fok said.

Since Britain handed Hong Kong back to Chinese rule in 1997, the communist mainland has gradually lifted restrictions on its citizens who come to freewheeling, capitalist Hong Kong.

Thousands of mainlanders have immigrated, through work or marriage, lured by Hong Kong's greater freedoms, wealth and opportunities.

Many pregnant women cross the border hoping to give birth in Hong Kong, where any child born is automatically considered a permanent resident and entitled to schooling, medical and other benefits.

Births by mainland Chinese women in Hong Kong jumped from 7,810 in 2001 to 25,482 in 2006, according to government statistics. Some Hong Kongers fear there will not be enough beds or staff for local women.

The government cracked down in February, imposing far-higher maternity fees on mainland women. Heavily pregnant women are also being refused entry if they cannot prove they have reserved a hospital bed.

A Hospital Authority spokeswoman confirmed Tuesday that the new measures aim to deter non-local pregnant women seeking last-minute admission to Hong Kong hospitals. She declined to comment on Fok's case because court procedures were under way, and she spoke on condition of anonymity, citing policy.

Social worker Edmond Wong urged the government to review the policy.

"Giving birth is a family issue," Wong said. "The policy is unfair to those Hong Kong families in which one of the family members is a Hong Kong resident."