About 10,000 houses in Christchurch may have to be demolished because of earthquake damage, while some parts of the city may have to be abandoned altogether, New Zealand's Prime Minister, John Key, said yesterday.

The magnitude 6.3 quake that hit on 22 February shattered homes, heritage buildings and office blocks and left at least 166 people confirmed dead. Officials expect the toll to top 200 as rescuers continue to search in the rubble.

Several hundred commercial buildings may have to be bulldozed, Mr Key said.