Women's rights advocates are looking for a fully fledged agency with a budget of $1billion on a par with other high-profile United Nations departments, to address crucial areas such as violence against women, property rights and HIV/AIDS.

The co-director of AIDS-Free World, and an advocate of gender equality, Stephen Lewis, said, ''[The UN] has neglected the rights and needs of women everywhere. It's clear to everyone that the marginalisation of women over decades is unacceptable and the best way to correct it is a UN agency like UNICEF for children.''

In sub-Saharan Africa, of the 63 million people with HIV, 60 per cent were women, and the percentage shot up to 75 per cent to 80 per cent in the 15-24 age group, he said.

Although the UN has poured billions into agencies for refugees and for children, women's issues are dealt with by several small departments that lack the resources of a fully fledged agency.

The idea for such a body emerged in 2006, from plans to reform the UN by the former UN secretary-general, Kofi Annan.

A high-level panel endorsed an agency headed by an under-secretary-general, one rank below secretary-general.

Rich nations favour creating an agency by the end of the year, but some members from the G77 group of developing countries, such as Cuba, Libya and Sudan, want to nail down issues such as governance and funding before agreeing to vote on a resolution.

How the agency will operate at country level with other UN bodies is an issue, as is the question of who will lead the new organisation. Mr Lewis is optimistic that the general assembly will pass a resolution to create the agency in September when it holds its annual session.

The aim to get $1billion will depend on the Obama Administration, which has yet to declare its position, and how much cash it will put in. Guardian