Key buildings in the city, struck by a shallow quake of magnitude 6.3 last Tuesday, are being scoured for bodies; the official toll is now 161.

The first foreign victims have been formally named - two Israeli tourists.

Power, transport and sewage systems are gradually being restored but rebuilding the city is a daunting task.

The Civil Defence national controller John Hamilton announced the shift from rescue to recovery "with considerable sorrow and frustration".

"We now face the reality that there is no chance that anyone could have survived for this long," he said.

Officials say the final toll could be as high as 240; the last person to be pulled alive from the rubble was found over a week ago, one day after the earthquake struck.