The head of the World Health Organisation (WHO), marking a year since the first cases of the novel coronavirus were reported by China, urged countries on Wednesday to ensure that vaccines are made available to people at risk everywhere, not just in rich nations.

WHO director-general Tedros Adhanom Ghebreyesus appealed for US$4 billion (RM16.1 billion) to buy Covid-19 vaccines for distribution in the lower and middle-income countries through the Covax vaccine facility.

"This is the challenge we must rise to in the...