Saudi Arabia has been elected to the United Nations Commission on the Status of Women, despite the country being ranked by human rights experts as one of the worst for gender equality.

The Middle Eastern kingdom was one of 12 new countries elected to the UN body in a secret ballot.

It will serve a four-year term beginning next year, according to a statement from the UN Economic and Social Council.

The role of the UN's Commission on the Status of Women is to promote gender equality and the empowerment of women.

According to its website, the body said it was "instrumental in promoting women's rights" and "documenting the reality of women's lives throughout the world and shaping global standards on gender equality".

But Human Rights Watch said Saudi women were forbidden from obtaining a passport, marrying or accessing higher education without the approval of a male guardian — usually a husband, father, brother, or son.

Saudi women are also banned from driving and are forced to have the permission of a male guardian to travel or work in the oppressive Middle East theocracy.

In a report last year, the NGO said "as long as it [Saudi Arabia] fails to take steps to eliminate the discriminatory practices of male guardianship and sex segregation, the Government is undermining the ability of women to enjoy even the most basic rights".

Asked about the election on social media, Former New Zealand prime minister Helen Clark, who recently retired from a high-level UN position as the administrator of the UN Development Program, said it was important to support those inside the country seeking to improve conditions for women.

Editor's note May 1, 2017: This story has been amended to clarify Helen Clark's response.