The controversy surrounding "Shuangfei" babies, referring to children delivered in Hong Kong by non-local parents, took a new twist on Wednesday, with the Hong Kong Special Administrative Region government agreeing to allow mainland women married to Hong Kong people to give birth at some local private hospitals.

Mothers of babies, neither of whose parents is a permanent Hong Kong resident, will be given extra quotas this year to give birth at four private hospitals provided they can produce relevant documents, but there are concerns over availability of beds and fees.

The 12-member Association of Private Hospitals had earlier agreed to a proposal by Chief-Executive-designate Leung Chun-ying to ban pregnant non-local women from private hospitals and refuse permanent residency for their children born here.

Secretary for Food and Health, York Chow Yat-ngok, said on Wednesday at least four private hospitals have agreed to accept pregnant women expecting to deliver in the coming months if there is sufficient proof of marriage to a Hong Kong resident.

The Hong Kong Special Administrative Region Health Department will then issue extra booking certificates to eligible mothers, whose number is estimated at no less than 100.

Tsang Koon-wing, organizer of pressure group, the Mainland-Hong Kong Families Rights Association, was skeptical on how many beds would be available at the four hospitals, coupled with the huge medical bills involved.

Chow said he had an "impression" that private hospitals will charge the mothers "affordable" fees, but the government cannot fix prices for private businesses. "They won't get more business if they refuse mainland women married to local residents anyway," he said.