Uneducated and unskilled youth are a "ticking time bomb" of pent-up emotions that will explode if not addressed soon, says Deputy President Kgalema Motlanthe.

"We have close to 2.8 million young people between the ages of 18 and 24 that are unemployed, and not in any institution of learning... this important social segment needs to pulled back into economic productivity as soon as possible," he said in a speech prepared for delivery at the 16th National Economic Development and Labour Council annual summit in Johannesburg on Friday.

According to a National Planning Commission report there were extremely high levels of illiteracy and innumeracy in schools throughout South Africa, and current growth projections were unsustainable for the economy's future, he said.

"Drastic measures" were needed to build an educated and skilled labour force, he said.

"We need to move beyond social dialogue... I believe that working together as partners we can do more to answer some of these challenges through incrementally building a pool of skills, know-how and knowledge base needed by the South African economy."