The Africa Union’s health watchdog on Thursday praised the United States’ support for a waiver on patent protections for COVID-19 vaccines as a “remarkable expression of leadership”.

“History will remember the move taken by the U.S. government as doing the right thing at the right time to fight a terrible challenge which is unprecedented in our contemporary history,” Dr. John Nkengasong, director of the Africa Centres for Disease Control and Prevention (Africa CDC), told a press conference.

As poor countries struggle to get enough vaccine doses, Washington’s Trade Representative Katherine Tai said Wednesday the country “supports the waiver of those protections for Covid-19 vaccines”.

“The extraordinary circumstances of the COVID-19 pandemic call for extraordinary measures,” she said in a statement.

Nkengasong hailed the move as “a remarkable expression of leadership and a very important development.”

“This development will continue to build a momentum necessary to enable us to achieve this goal. This is a step in the right direction,” he said.

Supporters of the waiver say that easing patent restrictions will spur production of low-cost generic vaccines, helping poor countries that are struggling to immunize their people.

Opponents argue the move will damage intellectual property rights and erode the profit incentive, ultimately affecting pharmaceutical research and development.