Scott Morrison reportedly unveiled his plan to help some Australians buy their first home more easily without consulting his cabinet.

Some of the prime minister’s senior colleagues only learnt of the idea when he announced it at the coalition’s election campaign launch on Sunday, according to the Sydney Morning Herald and The Age.

Under the new home deposit scheme, the government would offer loan guarantees for first home buyers, allowing them to buy properties with deposits of just five per cent instead of the typical 20 per cent.

Labor said it would match the scheme within hours of the coalition revealing it, but argues its proposed changes to housing tax breaks are needed to tackle the bigger picture of housing affordability.

About 10,000 people earning up to $125,000, or a couple earning $200,000, are expected to benefit each year under the new scheme.

That would have been about one in 11 new home-buyers in 2018.