Canterbury is set to get a cash injection for its mental health service.

The Government has vowed to pour millions of dollars more into fighting Canterbury's mental health problems.

Citing the recent spike in earthquake activity after the Valentines Day aftershock, Health Minister Jonathan Coleman says officials are working on a multimillion-dollar "extra package for mental health services".

The Canterbury District Health Board (CDHB)and clinicians have called for extra money to fight the rise in mental health issues since the 2011 earthquakes.

Coleman said: "As soon as the Valentine's Day quake hit I was sitting up in Auckland and thought, this is going to be big in terms of the health sector."

Director of mental health John Crawshaw was sent to Christchurch the next day to "assess the situation".

Coleman said officials had talked to CDHB chief executive David Meates, who backed the package.

When asked whether the money would have been granted if the Valentines Day quake had not happened, Coleman said the circumstances had "changed".

"Things were on the path to recovery, but then you had that big jolt which caused everyone to reassess the situation."

The package would need to go through Cabinet before it was announced.

It is understood deliberations over the funding amount was continuing between the CDHB and the Ministry.

CDHB chair Murray Cleverley said the money would ensure "we are delivering a sustainable service".

However, he would not be drawn on whether the funding was a one-off injection, or support over time. The latter would be required with rising capital charges, and pressures on staff, he said.

"We are very happy for a one-off, and we tip our hats to that.... but we expect the ongoing support from the ministry.

"But we've got to be better at saying how we can be assisted."

Sue Bagshaw, 298 Youth Health Centre founder, said the news was "excellent", after leading calls for extra money in a letter to Coleman last month.

It was "crazy" that it had taken five years for funding to be granted, she said. The fine details would need to be worked out with urgency.

She hoped funding would be spread across the board, to secondary and primary care, with a particular focus on child and youth services.

Canterbury needed more school-based mental health support, and money to go towards wages for more employees, she said.

"Children's brains have been altered ... we have to reconstruct their sense of permanency."

However, others remained unconvinced.

CDHB board member Jo Kane said the Government was simply reacting to "something that gets too hot in the media".

"Quite frankly I'm sick of the reactionary funding packages we're getting. It's not a good way to do business.

"I wish there was a whole package for the whole health system."

While remaining coy about whether this had eased the relationship between the feuding CDHB and Ministry of Health, Coleman said they had the same "interest at heart" all along.

"My expectation is that people get on and work on the big issues... they don't need to go off and spend social time together.

"We've got to move on from the past and the tensions, either real or perceived."

He did not believe the money had taken too long to be approved.

"There has been support all the way through over these five years, people have received the services they needed.

"It's not like after day one, after a big earthquake, you can say 'In the next five years this is going to play out'."

BY THE NUMBERS:

Since the earthquakes there has been:

- a 43 per cent increase in adult community mental health presentations.

- a 37 per cent increase in emergency presentations.

- a 69 per cent increase in child and youth mental health service presentations.

- a 65 per cent increase in rural mental health presentations.