Prime Minister Jacinda Ardern encourages Kiwis to press for progress on International Women's Day

Prime Minister Jacinda Ardern has marked International Women's day with a plea for Kiwis to keep "pressing for progress".

In a video posted on her Twitter page she said she could not imagine a better year for the day to be marked with the theme, Press for Progress.

"Here in NZ we're celebrating 125 years of women's suffrage. We have, right now, in our Parliament the greatest representation of women we've ever had," she said.

"And yet there is still a need to press for progress."

She cited a gender pay gap which was "particularly significant" for Maori and Pacific women and high rates of domestic violence.

She encouraged women to keep striving for representation at the highest level but reminded people that was not where true equality was

"There is change that we still need. Let's remember that true equality is achieved when women are free from violence and when they have financial security."