"We are the only continent that has not gone through a green revolution and we are the only continent that cannot feed itself this is not sustainable," Annan told a news conference in Nairobi.

Annan said the Nairobi-based group hoped to replicate farm changes that boosted agricultural productivity in countries like India in the 1970s.

"I hope that in 10 to 20 years or so we will be able to double Africa's agricultural productivity," he said.

According to the United Nations, food insecurity in Africa is worsened by weak institutions, insufficient investment in agriculture by governments and donors, and a harsh environment made worse by climate change, corruption and mismanagement.

He said the group would focus on helping Africa's millions of small-scale farmers fight poverty and boost productivity by providing stronger and more resistant seed varieties, and improving access to farm inputs and markets.

Annan said the group would not seek to spearhead the use of genetically modified seeds, which have been a controversial subject in some African countries, but would use traditional methods to boost disease resistance of existing seeds.