April 26 (UPI) -- The United States will release AstraZeneca COVID-19 vaccine doses to other countries, official said Monday.

Andy Slavitt, White House senior adviser for COVID-19 response, made the announcement on Twitter.

"U.S. to release 60 million AstraZeneca doses to other countries as they become available," Slavitt tweeted.

The announcement comes amid mounting pressure from lawmakers and experts since the United States has millions of doses of AstraZeneca vaccine that is authorized in other countries, such as India, where the COVID-19 crisis is worsening. The vaccine is not yet authorized for use in the United States.

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