Nkosazana Dlamini-Zuma, the outgoing head of the African Union (AU), has hit out at Donald Trump's controversial immigration order at a summit in Addis Ababa, Ethiopia.

She said: "The very country to which many of our people were taken as slaves during the transatlantic slave trade has now decided to ban refugees from some of our countries."

South Africa's Dlamini-Zuma, the first woman to serve as the continent's top diplomat, described Trump's hotly contested travel ban as "one of the greatest challenges" for Africa. She warned that there were "very turbulent times" ahead for the continent.

"What do we do about this? Indeed, this is one of the greatest challenges to our unity and solidarity," she told members from the 54 African countries in the Ethiopian capital, according to Eyewitness News.

Former first lady Michelle Obama gave a speech at he Democratic National Convention (DNC) in July 2016, reminding her audience that the White House was built by slaves.

"That is the story of this country, the story that has brought me to this stage tonight, the story of generations of people who felt the lash of bondage, the shame of servitude, the sting of segregation, but who kept on striving and hoping and doing what needed to be done so that today I wake up every morning in a house that was built by slaves."

A report from the Pew Research Centre stated: "The US public has seldom approved of accepting large numbers of refugees. In October 2016, 54% of registered voters said the US does not have a responsibility to accept refugees from Syria, while 41% said it does. Around 87% of Donald Trump supporters say the US doesn't have a responsibility to accept Syrians."

Citizens of seven Muslim majority nations, including Syria, Iraq, Iran, Libya, Somalia, Sudan and Yemen, will be denied US refugee status or visas for the duration of the ban.

Antonio Guterres, the UN secretary-general, contrasted the different stance of African countries compared to the US. He said: "African nations are among the world's largest and most generous hosts of refugees. African borders remain open for those who need protection when so many borders are being closed, even in some of the most developed countries in the world."