(CNN) President Joe Biden, well on his way to reaching a new goal of vaccinating 200 million Americans by the end of April, is taking initial steps toward helping other nations ramp up shots, including by boosting global manufacturing and appointing a top global health expert who previously advocated for shipping vaccines from the United States' surplus abroad.
Diplomats view the developments as a sign Biden is moving toward sharing some of the hundreds of millions of doses the United States will have left over once every American is vaccinated. But the President remains wary of sending vaccines overseas before people in the United States have access, and administration health experts continue to caution that extra doses may be needed as the virus mutates and the pandemic persists.
Biden's political advisers and national security team have debated the appropriate balance among domestic needs, humanitarian efforts and political strategy, people familiar with the matter say. Meanwhile, State Department officials field near-daily requests from other countries for vaccines, according to diplomats, whose answer has largely been the same: no shipments until the US is taken care of.
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Biden himself has faced similar questions in telephone calls and virtual meetings with his foreign counterparts, who have pressed him on why the US is purchasing so much more vaccine than it would appear to need, according to people familiar with the conversations. Despite having already received vaccines from China or Russia, many of the countries calling with requests are making clear they want as many US or European vaccines as they can get.
Increasingly wary of efforts by Beijing and Moscow to use their vaccines to foster good relations in countries desperate to begin vaccinating their populations, and nearing a point when any American who wants a vaccine can get one, Biden and his team have begun developing more robust plans to ramp up assistance efforts abroad.
On Monday, Secretary of State Antony Blinken announced a new position for Gayle Smith, a former director of the US Agency for International Development, to coordinate the international response to the coronavirus pandemic. Smith had most recently been the CEO of the ONE Campaign, which has been vocally pressuring Biden's administration to ship some of the US vaccine supply abroad. Her appointment is an indication that the administration is now in a place to start thinking about how to share vaccines, an administration official said.
US diplomats said they expected more internal discussions in the coming weeks about where the US should send excess vaccines. The eventual decision -- which administration officials said could still be months away -- will take into account a variety of factors, such as US interests in different regions and Covid-19 levels in individual countries. South and Central American nations are seen as particularly critical because of the current migration surge to the US, according to officials and diplomats, but no decisions have been made yet about where excess vaccines will go.
For now, the White House says it must retain enough vaccines in case of unforeseen developments in the pandemic.
"Why aren't we at the point where we are sharing doses with every country around the world? Part of it is because we need to plan for things coming up," White House press secretary Jen Psaki said on Monday, citing a recent mix-up at a plant producing the Johnson & Johnson vaccine that resulted in 15 million ruined doses.
"We have to plan for a range of contingencies. That's exactly what we did," she said. "That's one of the many reasons that we are going to still be in a place where we held enough vaccines for adult Americans by the end of May."
Last week, Psaki said that conversations about sharing US vaccine doses would occur eventually.
"As we get increasing confidence that we have enough vaccine, we will explore options for sharing more broadly," she said.
Competing with China, which has already given vaccines to dozens of countries, will be a significant challenge, officials acknowledged. But given the global demand and desire for US and European vaccines, Biden administration officials do not think it is too late for the US to step up to the plate.
Speaking Monday, Treasury Secretary Janet Yellen said rich nations must help speed the vaccine roll-out in poorer countries, warning that failing to contain the virus abroad would deepen inequality and wind up damaging the US.
"Unless we act now, the world is susceptible to the emergence of a deepening global divergence between rich and poor countries," she said.
The US has announced separate financial commitments to entities tasked with producing and distributing the vaccine in developing countries -- including $4 billion to Covax, an international consortium -- and a pledge to help expand vaccine production in India with the aim of distributing the product elsewhere in Asia.
The US also has provided limited shipments of AstraZeneca's product -- which is not yet authorized for use in the United States -- to Mexico and Canada, whose leaders had each raised the subject with Biden during virtual summits over the past two months.
Still, Biden has so far stopped short of sending ready-to-use doses of the three vaccines being distributed in the US -- Pfizer, Moderna and Johnson & Johnson -- to countries that need them. He has resisted calls to loosen intellectual property rules in order to allow other countries to begin producing vaccines.
He is also facing pressure from a variety of global voices to step up his efforts to get more of the world inoculated.
Alfonso Quiñónez, Guatemala's ambassador to the United States, said in an interview that more money to purchase vaccines wasn't a problem. Instead, he said accessing vaccine supplies has been a challenge because of global demand.
"If our population doesn't get to be vaccinated -- and every day are coming into the United States a number of Guatemalans that are not vaccinated yet -- the risk continues to exist here in the United States," he said.
"We're not asking for donations," he added. "We have resources to purchase them but, right now, the international market is too hot for vaccines."
The US government has purchased far more vaccine doses than would be necessary to provide shots to the entire population of the country, spreading out the orders among the three currently authorized and AstraZeneca. Biden's team has been wary of releasing already-purchased doses for a variety of reasons, both political and practical, according to people familiar with the matter.
Polling by the Pew Research Center conducted in February showed that a vast majority of US adults -- 66% -- believed the US should ensure there are enough vaccines available in the United States, even if that meant developing countries must wait longer. That was the majority view among both Democrats and Republicans.
But officials have cited the still-uncertain nature of the virus, which has been mutating and continues to spread in the United States, as a primary reason for keeping an overstock of doses instead of shipping them overseas.
Officials said the possibility of more variants, and the prospect of requiring booster shots in the future, is driving some of the reluctance to distribute more of the US vaccine supply abroad, even though the administration expects a surplus of doses.
Biden's health advisers are also waiting to see which vaccine works best on adolescents and children, and don't want to send doses abroad before knowing which shot will be recommended once testing is complete and those age groups become eligible. That could still be months away, and officials said they did not want to be in a position where they have shipped a vaccine overseas that is suddenly needed for American kids.
The political downsides of sending vaccines abroad are also woven into the administration's decision-making. Biden's team recognizes the imperative in making vaccines available to Americans before sending them abroad, and the President himself has made clear to his team that his focus right now is on the US vaccination efforts.
"If we have a surplus, we're going to share it with the rest of the world," Biden said last month. "We're going to start off making sure Americans are taken care of first, but we're then going to try to help the rest of the world."
Officials believe the political downside to sharing vaccines will wane as availability ramps up in the US. Officials view early May as the moment when most Americans will have access to shots, making it more palatable to distribute vaccines overseas.
It is unclear what percentage of Americans need to be vaccinated before the Biden team will decide to start sharing vaccines with other countries, but that discussion is expected to take place in the coming days and weeks, administration officials said.
Smith, the new coordinator, will engage in interagency discussions to determine what sharing with other countries is going to look like and when the administration is ready to start doing that, administration officials said. The ONE Campaign, the organization Smith was running previously, has called for 5% of the US supply to be shared abroad once 20% of the US population is vaccinated.
"As we get more confident in our vaccine supply here at home, we are exploring options to share more with other countries going forward," Blinken said at the State Department on Monday, announcing the new appointment. "We believe that we will be in a position to do much more on this front. I know that many countries are asking for the United States to do more, some with growing desperation, because of the scope and scale of their Covid emergencies. We hear you, and I promise we're moving as fast as possible."
National security officials in the administration recognize the value in providing vaccines abroad -- diplomatically, strategically and healthwise. But because the President's views on getting Americans vaccinated first are firm and well-established, few internal disputes on the matter have broken out, aides said.
The US has already been providing some direct Covid-19 support. For example, in Colombia the US donated isothermal transport kits, which allowed 1.2 million vaccine doses to be transported to remote regions of the country.
The top US diplomat said Monday that the United States would not "trade shots in arms for political favors" but did not offer specific details on the administration's plans to share vaccines more broadly beyond its immediate neighbors.
Blinken also outlined other "core values" he said would guide the State Department's plans, in what appeared to be a swipe at Russia and China: "We won't overpromise and underdeliver. We'll maintain high standards for the vaccines that we help to bring to others, only distributing those proven to be safe and effective. We'll insist on an approach built on equity."