The Biden Administration has announced plans for the U.S. to share its full supply of AstraZeneca (AZN  ) vaccine with the rest of the world as soon as the Food and Drug Administration (FDA) finishes a safety review of the doses.

"Given the strong portfolio of vaccines that the U.S. already has and that have been authorized by the FDA, and given that the AstraZeneca vaccine is not authorized for use in the U.S., we do not need to use the AstraZeneca vaccine here during the next several months," White House COVID-19 coordinator Jeff Zients told the Associated Press (AP). "Therefore the U.S. is looking at options to share the AstraZeneca doses with other countries as they become available."

Prior to this decision, the White House had been facing pressure and condemnation for refusing to share its supply of AstraZeneca vaccines. Up till now, the country has sent just four million doses to countries in need, out of their contracted 300 million doses.

Currently, the U.S. has roughly 10 million fully produced doses and an additional 50 million doses in various stages of production. The 10 million produced doses are awaiting approval by the FDA.

The FDA is conducting this final review to ensure that the doses "meet its expectations for product quality," according to Zients. The approval process could take several weeks. This additional review is seen as necessary due to issues at the vaccine's production facilities. Due to those issues, the AstraZeneca vaccine will now need to be produced at an as yet to be decided U.S. production facility.

The four million doses that have already been donated were sent to Canada and Mexico, but the full 60 million that the U.S. hopes to distribute in the coming months have been requested by dozens of countries, according to the AP. The destination of the donated vaccines has yet to be determined.

"We're in the planning process at this point in time," White House press secretary Jen Psaki told AP.

Vaccination rates in the U.S. have reached 53% amongst adults, and demand for the vaccine has dropped considerably. Meanwhile, vaccine doses are in short supply throughout the rest of the world.

India in particular has been facing a brutal wave of new coronavirus infections with roughly 2,500 people dying of the virus every day. The Biden Administration recently faced considerable heat for refusing to share supplies with India, a decision which was reversed on Sunday. To reiterate, these materials are used to create the AstraZeneca vaccine, a vaccine which is unlikely to be administered to many Americans.

The U.S. is among the top four vaccine producers in the world, but unlike its contemporaries, the U.S. has kept almost all of its vaccines at home. This decision and attitude has been dubbed "vaccine nationalism" by countries throughout the world, many of which haven't been able to start vaccinating at all.

In addition to withholding vaccines, President Joe Biden also utilized the Defense Production Act in order to ensure that U.S. manufacturers would have priority access to the materials needed to produce vaccine doses. The Administration has made it clear that they will place American needs above other priorities, including by storing spare doses for later domestic needs.

However, for those critical of the Administration's decision to delay helping other countries, White House COVID-19 advisor Andy Slavitt had this to say in a tweet.

"To everyone who understandably says: 'about time' or 'what were they waiting for', at this time there are still very few available. No real time has been lost."

Of course, with death rates in the thousands and vaccine rollouts stalling around the globe, when it comes to fighting this global pandemic, every day is essential.