Higher food prices risk wiping out progress towards reducing poverty and, if allowed to escalate, could hurt global growth and security, United Nations Secretary-General Ban Ki-moon said on Sunday.

Opening a UN trade and development conference in Ghana, Ban pledged to use the full force of the world body he heads to tackle the price rises, which threaten to increase hunger and poverty and have already sparked food riots in Asia and Africa.

"I will immediately establish a high-powered task force comprised of eminent experts and leading authorities to address this issue," Ban said, after a group of the world's 49 least developed countries called on Saturday for such a team.