US President Joe Biden said his administration will donate an additional 17 million doses of the Johnson & Johnson (J&J) vaccine to the African Union after criticism that the US is not being more generous.

Biden made the announcement in a meeting Thursday with Kenyan President Uhuru Kenyatta at the White House. Delivery of the single dose of the J&J vaccine is expected to take place in the coming weeks, a senior administration official said.

These new doses will be in addition to another 50 million coronavirus vaccines that the administration has already committed to supplying the African Union.

Kenyatta thanked for the promise, saying that the US had done its best to "do its best" to help Africa get vaccines.

The Biden administration sees the donation as a mechanism to help close a gap in vaccine equity, in which populations in wealthier nations have greater access.