The Government is taking aim at 43,000 solo parents who it says should go back to work.

Prime Minister John Key and Social Development Minister Paula Bennett have this afternoon unveiled a major package of welfare reforms.

Ms Bennett said that for some beneficiaries "the dream is over".

There were 43,000 single parents on the domestic purposes benefit whose children were of a school age and who were ready to transition back to work.

"We expect those people to be at work for at least 15 hours a week," Ms Bennett said.

There were many solo parents who worked and brought up their children without state support.

Ms Bennett and Mr Key also announced some 9000 sickness beneficiaries would be asked to go back into part-time work.

"We will expect them to do what they can to support themselves. We want people to focus on what they can do and not on what they can't," Ms Bennett said.

Further changes included:

- Requirement for people on the unemployment benefit for 12 months to reapply.

- More graduated sanctions for people who don't comply with their work obligations.

- An increase in the amount that people on the DPB and Invalids Benefit can earn each week, without affecting their benefit, from $80 to $100.

- More frequent reassessment for people on the Sickness Benefit.

Ms Bennett said she was worried too many people viewed welfare not as a last option but as a way of life.

The unemployment benefit was a temporary benefit for people temporarily unable to find work.

If people had shown a "real demonstrable effort" to find work after one year, their benefit would be reinstated.

"If not, well, I'm afraid the dream is over," Ms Bennett said.

Emergency hardship payments would also be tightened up.

"We're tightening the system up so that these payments only go to those in genuine need to those whom life has simply thrown one too many curve balls."

The Government could not sustain the $250m it paid in hardship payments last year.

Mr Key said he and Ms Bennett had a "healthy amount of first-hand experience" with the welfare system which meant they had a strong commitment to it.

"While these reforms will improve the benefit system, there is still more work to be done," Mr Key said.

"The Government remains concerned about the prospects of a growing welfare roll in the decades ahead, accompanied of course by an increasing welfare bill."