Australia will make it more difficult to gain citizenship in a major overhaul of its migration process.

Aspiring citizens will undergo tougher tests on their English language skills and ability to demonstrate "Australian values", PM Malcolm Turnbull said.

Applicants must also have completed four years as a permanent resident - three years longer than at present.

The move comes two days after Australia unveiled stricter visa requirements for skilled workers from overseas.

Mr Turnbull said the changes would ensure that migrants were better integrated into the community.

"It is important that they understand that they are making a commitment to our Australian values," he said.

What are the changes?

In explaining what constituted "Australian values", Mr Turnbull said migrants must demonstrate support for religious freedom and gender equality.

"Respect for women and children ... that is a key Australian value," he said, adding domestic violence would not be tolerated.

Other changes to the citizenship process include:

•    A more stringent English language test involving reading, writing, listening and speaking;
•     Providing evidence of integration into the community, such as employment history, school enrolment or membership of community organisations;
•     Having already been a permanent resident for at least four years;
•     Allowing applicants to apply only three times, and automatically failing anyone who cheats on a test.

When asked about reports that applicants would be quizzed on whether they supported forced child marriage or female genital mutilation, Mr Turnbull said it was important to "reinforce our values".

"If we believe that respect for women and children [is an Australian value]... then why should that not be made a key part, a fundamental part, a very prominent part, of our process to be an Australian citizen?"

Tightening rules

The requirements would apply to all new applications for citizenship, the government said.

On Tuesday, the government said it would replace a controversial visa scheme to make it harder for foreign nationals to work in Australia.

Mr Turnbull said both announcements had been made in the national interest.

The opposition Labor Party accused Mr Turnbull of making announcements for political gain.

"It seems a little odd to me that you would actually ask people whether or not they are going to obey the law when they already pledge to obey the law," said Labor senator Penny Wong.