Apple has said it will soon be producing one million face shields a week for medical workers battling the coronavirus pandemic.

The tech giant had already sourced 20 million surgical masks from around the world to help address a global shortage, chief executive Tim Cook said in a video posted to Twitter on Sunday.

But the company had also designed its own transparent protective face shield and begun mass production at its factories in the US and China, he added. "We plan to ship over one million by the end of this week," said Cook.

Initial distribution would be focused on the US but the company hoped to "quickly expand distribution" to other countries, he said.

Apple joins several global firms that have modified their production lines to meet demand for protective gear, including Italian luxury brand Prada.

US President Donald Trump last month issued a federal order forcing auto giant General Motors to manufacture ventilators after a shortage of the hospital equipment, which is crucial for treating critical COVID-19 cases.