"Mental health will be a cornerstone of the government's budget," Jacinda Ardern said (File)

The New Zealand government will deliver its first ever "Wellbeing Budget" this week, said Prime Minister Jacinda Ardern on Monday.

Instead of meeting GDP goals, this year's government budget is understood to be focused on social issues such as mental health, homelessness and child poverty, reports Xinhua news agency.

"Mental health will be a cornerstone of the government's budget," Ardern told the media.

"This demonstrates our spending parameters for this budget, which a lot of investment has been shared over the past months as we made announcements to tackle the long term challenges facing New Zealand and to improve the well-being of all of us."

The New Zealand coalition government is committed to putting people's well-being and the environment at the heart of its policies, including reporting against a wider set of well-being indicators in future Budgets, it was said in last years' budget.

The government will announce its annual budget on Thursday.