Hundreds of people displaced by Tuesday's earthquake have set up camp at Christchurch welfare centres and more are flooding in.

A desperate plea for rescue by six Filipino nurses trapped inside the CTV building have emerged following fears up to 120 people are still entombed in one of the focal points of Christchurch's deadly earthquake.

Hopes of finding survivors in the rubble of Christchurch are fading as the second day following the devastating quake draws to a close.

A 52-year-old man is in a stable condition after having both legs amputated by a visiting surgeon at the PGC building.

Credit rating companies say there is no immediate need to change the credit ratings of insurers because of the Christchurch earthquake but Moody's Investors Service said ratings pressure may develop over time on the banking sector.

Rescuers will do everything humanly possible to find any survivors of Tuesday's destructive Christchurch earthquake, say police.

There is no possibility of survivors in the rubble of the Christchurch Cathedral, police said this afternoon.

Labour leader Phil Goff has been in Christchurch surveying the earthquake damage.

There are 76 dead in the temporary morgue set up by police in Christchurch and more coming "in ones and twos", Police Minister Judith Collins said as she praised the efforts of rescue workers this afternoon.

Police and security staff are worrying about the possible further collapse of building facades.

More bodies have been recovered from the collapsed CTV building in Christchurch.

Personnel at the PGC building in Christchurch have switched their focus from trying to find survivors to recovering the dead, the company says.

An ASB Bank economist says she expects Reserve Bank governor Alan Bollard to cut the official cash rate by 50 basis points to 2.5 per cent in part due to the economic impact of the Christchurch earthquake.

Christchurch earthquake - reaction, thoughts, pictures from social media in New Zealand and around the world.

FIFA president Sepp Blatter has sent a letter of support to New Zealand Football chairman Frank van Hattum following the Christchurch earthquake.