'Ignore the sexist attack' - Helen Clark's advice to Jacinda Ardern

Former Prime Minister Helen Clark has waded into the debate about new Labour leader Jacinda Ardern and her plans to have children.

Ms Clark has taken to Twitter, saying her number one piece of advice to the new Labour leader is to ignore it all and just "get on with the job".

Ms Clark also questioned why male politicians aren't asked why they don't have children, and when they plan to.

She says it's a pattern of behaviour which amounts to gender-based attacks.

"Ridiculous in 21stC that #women in leadership positions are subjected to gender-based attacks. Are those who make them proud of themselves?" the ex-Labour leader wrote.

In another tweet, she said being a politician and having children would be possible in a fair and equal society.

Ms Clark was often faced with criticism over her decision not to have children.

"Having children has never been something I've wanted to do because I value my personal space and privacy too highly," she said in 1993.

"I cannot think of the sort of life I would want to have where I would want to give up those things for children."

She later described attacks from political opponents about her lack of children as "pathetic".

Ms Clark was Prime Minister for nine years between 1999 and 2008.

Present Prime Minister Bill English has six children.

Newshub.