Britain's Prime Minister David Cameron, President Susilo Bambang Yudhoyono of Indonesia and Liberia's President Ellen Johnson-Sirleaf will lead a global panel to set international targets on sustainable development, UN chief Ban Ki-moon said Wednesday.

The panel will start work after a major summit next month in Rio de Janeiro. The trio admitted in a joint statement that there was still "some way to go" to eliminate global poverty.

"I am grateful to these three leaders for their commitment," Ban said in announcing the panel which will set new targets to replace the Millennium Development Goals.

The eight Millennium goals aimed to eliminate poverty and boost health in poor countries by 2015, but many will not be met. Negotiators from around the globe are now discussing how to set new goals which will also set targets for improving the green economy and saving the Earth's resources.

Cameron, Johnson-Sirleaf and Yodhoyono issued a joint statement in which they said they wanted "to set out an ambitious, new agenda for ending poverty in the years beyond 2015."

They praised the MDGs for "helping to put millions of children into school and save countless lives.

"We still have some way to go, but we also want to build on what has been achieved so far. In the years since the MDGs were agreed, we have made significant progress and learned many lessons on how to reduce poverty.

"We now know more about the critical role that economic growth, trade, tackling corruption, effective government and open societies play in creating wealth and unlocking the potential of the poorest countries."

Ironically, Cameron will not be attending the Rio summit at the end of June. He is instead sending Deputy Prime Minister Nick Clegg. German Chancellor Angela Merkel and probably US President Barack Obama will also miss the meetings.

The UN has still said that about 110 heads of state and government are expected at the summit, which is officially to mark the 20th anniversary of the Rio Earth summit.

Ban said the sustainable development agenda was "vital work."

"In virtually all of my meetings with world leaders I have emphasized the historic importance of the Rio+20 conference and urged participation at the highest level," he said.

"I have been pleased by the response. We expect a high number of heads of state and government to attend," added the UN leader.