All African countries now have laboratories that can process coronavirus tests, the head of the World Health Organization (WHO) said.

Dr Tedros Adhanom Ghebreyesus had earlier advised countries to consider their ability to test and trace before easing any lockdown measures.

During a virtual conference to discuss the development of a Covid-19 vaccine, Dr Tedros also warned that the pandemic was accelerating.

"The most recent one million cases of Covid-19 were reported in just one week," he said.