Kenya has been criticised for the release of controversial national census figures that include tribal affiliations.

The country announced on Tuesday that its population stands at 38.6 million after a national census conducted last year, marking an increase of around 10 million since the last census in 1999. The new figures showed its five most populous ethnic groups being the Kikuyu, Luhya, Kalenjin, Luo and Kamba.

The decision has been criticised by some as stoking ethnic divisions. But the director of Kenya's census said it was better to have indisputable facts on Kenya's ethnic make-up than politically motivated claims from the groups themselves.

Planning Minister Wycliffe Oparanya admitted there had been controversy over what figures to release. "There was a lot of debate on whether to include ethnicity in the census, but we have decided to be transparent," he told Kenya's East African Standard newspaper.

In Kenya’s post-election violence in 2008, more than 1,000 Kenyans were killed and roughly 300,000 made homeless.