At that summit, G8 nations had vowed to raise annual aid levels by $50 billion by 2010, $25 billion of which was for Africa. This was reiterated at last year's summit in Heiligendamm, Germany.

But aid workers and NGOs had expressed concern about the pledge, saying donor countries might fail to meet their promises, which are not legally binding and are hard to track in actual spending.

"We are firmly committed to working to fulfil our commitments on ODA made in Gleneagles, and reaffirmed at Heiligendamm, including increasing, compared to 2004, with other donors, ODA to Africa by $25 billion a year by 2010," the G8 said in a statement on Development and Africa, referring to overseas development aid.

The G8 chiefs also said they acknowledged aid from the group and other donors should be reassessed and might need to be increased for the period after 2010, beyond their current commitments.

African development, as well as the food crisis and climate change, is high on the agenda for the three-day G8 summit that ends on Wednesday in Hokkaido, northern Japan.

The group also said they were determined to honour in full their specific commitments to fight infectious diseases, such as malaria, tuberculosis, polio, and working towards the goal of universal access to HIV/AIDS prevention, treatment and care by 2010.