Moderna plans to invest up to $500 million to build a factory in Africa to make up to 500 million doses of mRNA vaccines each year, including its COVID-19 shot, as pressure grows on the pharmaceutical industry to manufacture drugs on the continent.

African countries and the World Health Organization (WHO) have been urging drugmakers for months to set up vaccine plants on the continent to help it secure supplies of COVID-19 shots that have been hovered up by wealthier nations.

As of Thursday, only about 4.5 percent of Africans had been fully vaccinated against COVID-19, according to the continent's top public health official, John Nkengasong.

Moderna proposed site is expected to include drug substance manufacturing as well as bottling and packaging capabilities. The U.S. drugmaker said it would begin the process of deciding the country and location soon.

"We expect to manufacture our COVID-19 vaccine as well as additional products within our mRNA vaccine portfolio at this facility," CEO Stephane Bancel said in a statement.

Nkengasong, director of the Africa Centers for Disease Control and Prevention, said he had not seen the Moderna statement and the company had not consulted with him.

At a news conference, he welcomed any efforts to address the continent's medium- to long-term needs, but said Moderna's plans would not solve its problems securing COVID-19 vaccine doses now.

(With input from agencies)