Security officials have rejected calls to verify the number of mainland children who were estimated to be eligible for right of abode in Hong Kong before the reinterpretation of the Basic Law in 1999.
They said it would send a 'very wrong message' that the immigration policy would change.
Legco security panel members made the calls yesterday after discovering only 150,000 of the 270,000 mainland children the government now estimates are eligible to settle in the city have done so since the handover.
A Census and Statistics Department estimate in May 1999 said there were 1.67 million mainland children of Hong Kong residents. The figure was later revised to 1.6 million.
But after a reinterpretation of the Basic Law on June 26, 1999 - a move that overturned a Court of Final Appeal verdict in favour of abode seekers - most of the 1.6 million mainland children became ineligible as their parents were not Hong Kong permanent residents at the time of their birth.
The government then revised the estimate to 270,000.