The Prime Minister believes Christchurch is receiving enough funding for mental health patients.

Today marks five years since a 6.3 magnitude quake struck Christchurch, killing 185 people.

This sparked a surge in Cantabrians requiring mental health treatment and the government responded by injecting millions into Christchurch mental health with $3.75 million budgeted for psychological services in 2015/16.

John Key praised the rebuild progress on TVNZ's Breakfast this morning and said Cantabrians aren't and won't be missing out on mental health treatment.

"The funding cut is a myth, it's just not true," he said.

When asked why funding for psychological services has decreased from 1.6 million to $200,000, Key said: "Where people back fill numbers is they say as a ratio of the population to mental health services, you're putting in less money."

He said the city's population has increased post-quake, with many not requiring mental health treatment.

"Yes there is a demand for mental health services, yes that was a thing that spiked after the aftershock last week," Mr Key said.