UN Secretary General Ban ki-Moon on Monday called on world governments to work with the United Nations to vastly improve women's and children's health by 2015.

"Our joint action plan demands that all women and children should benefit from the relatively simple, proven health practices and known technologies that save lives," Ban said as he announced a global action plan for women's health in a speech to open the Women Deliver conference on women's health.

"We must fight for women's health with all our resources, all the time. When we work together, we succeed," Ban said at the conference in Washington.

US Secretary of State Hillary Clinton was expected to address the gathering later Monday by video, and Melinda Gates, wife of Microsoft co-founder Bill Gates, was due to announce major funding for women's and children's health initiatives from the Bill & Melinda Gates Foundation.

Over three days, some 3,500 conference participants from 140 countries will look at progress that has been made in improving global maternal health and assess the challenges that remain.

Participants were expected to include the former presidents of Chile and Ireland, Michele Bachelet and Mary Robinson, as well as actress and women's advocate Ashley Judd.

They will call on governments and private donors to commit at least 12 billion dollars to address maternal, reproductive, and newborn health around the world.

The target date of 2015 outlined by Ban was set in 2000, when world leaders drafted a plan known as the Millennium Development Goals, which aim to meet specific targets in fighting hunger and poverty, and improving health care and education.

Promoting gender equality and empowering women is one of the Millennium Goals.