By Jonathan Davies

Taxi-booking app Uber has promised to sign-up one million female drivers by 2020.

Uber made the announcement through a blog post by chief executive Travis Kalanick, which was signed by Phumzile Mlambo-Ngcuka, a United Nations Under-Secretary-General and the Executive Director of UN Women.

Although global figures on female drivers aren't known, Uber says around 14% of its 160,000 drivers in the US are female.

The promise comes after of negative headlines for Uber in which some of its drivers have been accused of assaults on women in some cities.

The statement from Mr Kalanick and Ms Mlambo-Ngcuka said: "Today, UN Women and Uber are launching a partnership to work together around the world toward a shared vision of equality and women’s empowerment."

"This important mission can only be accomplished when all women have direct access to safe and equitable earning opportunities.FIFA Ultimate Team Coins We look forward to a partnership where UN Women and Uber will drive more access to these types of opportunities around the world," they added.