WASHINGTON (AP) — Millions of coronavirus vaccine doses are in cold storage in the U.S. that can’t be injected in the states because they are not yet approved by the Food and Drug Administration. But the Biden administration is not yet allowing those doses to be sent overseas, where American allies are struggling to get enough vaccine for vulnerable populations. U.S. partners are prodding President Joe Biden to release supplies of Astra Zeneca’s vaccine that are sitting idle, noting that the administration has lined up enough doses of the three already-approved vaccines to cover every American adult by the end of May and the entire U.S. population by the end of July.