More than 80 per cent of the cordon around Christchurch's earthquake-ravaged central business district (CBD) has been lifted to allow controlled access, Civil Defence says.

National controller Steve Brazier said Civil Defence had made significant progress in opening the cordoned areas due to staff working overtime and good planning.

More than 510 businesses, or 2000 people, have been granted access to buildings within the cordoned area.

Civil Defence expects remaining zones, excluding the worst-hit red zone, to be opened over the next three weeks.

However, no timeline could be guaranteed.

"We are fully sympathetic to the situation but we cannot put lives at risk to meet an artificial deadline.

"These dates will change in the event of unforeseen circumstances, such as a major aftershock or demolition delays," Mr Brazier said.

Civil Defence was working to create "safe corridors" to buildings within the red zone of the CBD from next week.

Tensions between Civil Defence and frustrated inner-city business owners seem to be easing after Civil Defence Minister John Carter and Mr Brazier met business groups following several heated protests.

However, some Christchurch business owners have reported returning to their businesses to find stock missing and have pointed the finger at demolition companies.

A central-city business owner said he had seen demolition companies take native timber from his demolished building. It was not about a few thousand dollars worth of wood but the principle of the action, he said.

"The issue is here that there is a wholesale mandate for looting to go on for contractors. Material has been taken and had we not been there and seen what happens then this would have gone on unbeknownst to us," he told Radio New Zealand.

Police have said they are investigating complaints about looting in the central city but could not comment in detail.

Mr Brazier said security was in place to prevent looting, including roving police controls.

Meanwhile, Christchurch residents who have lost homes and jobs because of last month's earthquake are desperately seeking financial help, with some saying money is taking too long to come through.

The Red Cross has received more than 37,000 applications for help - nearly four times greater than expected. Its quake appeal chairman, Sir John Hansen, said the numbers were "mind-boggling".

He said he had expected about 10,000 applications, with about $12.5 million to be paid out, but so far there had been more than 37,000 pleas for help.

The Red Cross had paid out more than $20m to more than 20,000 people and grant applications were continuing to pour in with about 2500 claims a day. The deadline for emergency help from the Red Cross is April 11.

So far, $46.33m had been donated to the fund, on top of the $10m left over from post-September quake donations, The Press reported.

Some residents were unhappy about the time it has taken to get help.

Sir John said the Red Cross was processing the claims as fast as it could.

Residents continue to face bad news with hundreds now dealing with job losses.

Twenty-four Christchurch Arts Centre staff have lost their jobs as have hundreds of hotel workers. Almost 100 Hotel Grand Chancellor employees, including waiting and service personnel and chambermaids, lost their jobs today. The building will need to be demolished but the owners plan to rebuild in Christchurch.

The Latimer Hotel will be closed for a year, according to its website, and is understood to have cut 70 staff, including some part-time workers.

Millennium & Copthorne Hotels has also made more than 100 staff - from three city hotels - redundant.

However, some central-city hotels will reopen when the cordon is lifted, including The Marque and the Novotel, an industry observer said.

Australian Foreign Minister Kevin Rudd visited Christchurch this afternoon before talks with kiwi counterpart Murray McCully.

Mr Rudd met Australian personnel assisting with earthquake recovery.

"Coming from Queensland, I know all too well the terrible toll that nature can exact," Mr Rudd said in a statement.

"Canterbury and Queensland are working hard to recover from the earthquake and floods and show the rest of the world that they are open for business."

Mr Rudd and Mr McCully will meet tonight and tomorrow for their twice-yearly meeting.