Key told a news conference Monday that the fitness of AMI Stadium would determine whether the southern city, struck by a deadly magnitude 6.3 earthquake on February 22, could host World Cup matches as scheduled.
"The biggest issue is ultimately the stadium," Key said. "There's some damage to the Deans Stand, some damage to the Hadlee Stand, there's some liquefaction outside and the turf has liquefaction damage which means it needs to be rebuilt - and that takes quite a number of months."
He said Christchurch's chance of hosting five group matches and two quarterfinals was not "looking bleaker" but there were several issues to be addressed before a definite answer could be given.
Keys said if the problems with the stadium could be fixed, then other logistical issues could be addressed.
"In the end, if we can get a stadium that operates and everyone is comfortable with then ... we need to deal with accommodation issues and with bars, restaurants and the like.
"I think we can address those issues, but we can't do that unless we have a stadium that gets a tick off."
Key said his Cabinet "understands the significance, if possible, of wanting to have the World Cup games hosted in Christchurch.
"The final decision ... is made by the IRB (International Rugby Board), we are working very closely with them on all of those issues," he said.
"We will have ... a clearer picture from an engineering perspective on whether AMI Stadium can (have) any structural issues remediated and be in a better position on whether we can get public liability insurance and the likes within a few weeks."
