Why a lack of vaccine cooperation with Mexico could put people on both sides of the border at risk The White House says more vaccine will not head south of the border on the same day Biden says both countries must “stand together” in a meeting with López Obrador. 7:27 PM on Mar 1, 2021 CST EL PASO — President Joe Biden told his Mexican counterpart, Andrés Manuel López Obrador, that both countries are better off when they “stand together” in a virtual meeting Monday shortly after the White House said the U.S. would not consider a request to share its coronavirus vaccine supply with its southern neighbor.