“To the extent that this is a backdoor to do that using our own government, we should not view that sanguinely, but we should be very concerned,” he said.

An Amazon spokesperson rejected the idea that the company’s offer was motivated by a desire to gain competitive leverage or stir up good publicity. The spokesperson, noting that Amazon made a similar offer to states last month, said it’s a matter of public responsibility for corporations to lend their help to the health crisis.

“There are things that we as a country will have to do to get through this pandemic and that includes lending our experience and expertise on things like logistics and the testing program we built,” the spokesperson said.

It’s unclear how seriously the new White House is taking Amazon’s offer, which a company spokesperson said is still being finalized. A White House representative, when asked about the administration’s view, noted the vaccination effort represents a “tremendous challenge” that will require “public, private and non-profit sectors working together to provide the solutions we need at the scale that we need them.”

Amazon’s bid comes as Biden officials say they are scrambling to repair a vaccine distribution system they’ve inherited from the Trump administration. Jeff Zients, Biden’s Covid-19 coordinator, this week complained that officials have limited ability to monitor vaccine allocations and distribution. Biden has pledged to mount a robust federal vaccination effort after former President Donald Trump pushed most of the work onto states, who say they’ve had little insight into the nation’s vaccine supply.

In Amazon’s letter to Biden, head of global operations Dave Clark said the company’s scale “allows us to make a meaningful impact immediately in the fight against COVID-19.” The company, Clark wrote, is “prepared to leverage our operations, information technology, and communications capabilities and expertise to assist your administration’s vaccination efforts.”

It’s a potentially attractive offer, some say. Nancy Foster, vice president of quality and patient safety policy for the nation’s largest hospital lobby, the American Hospital Association, said the vaccination effort needs more “expertise in managing significant logistical challenges.”

“We welcome announcements like this from Amazon that will help get more shots into arms across the country,” Foster said.

The Trump administration enlisted major companies to help distribute vaccines. It contracted with UPS and FedEx to handle ground shipping, American Airlines on air freight, and McKesson for distributing Moderna’s shot. Experts said a government collaboration with Amazon could prove beneficial if the company fills existing supply chain gaps.

Other corporate giants joined the vaccination effort this week. In Washington state, Democratic Gov. Jay Inslee partnered with Starbucks, Microsoft, Costco and others to help with the state’s rollout. Amazon is also opening a pop-up vaccination site at its Seattle headquarters on Sunday, aiming to administer 2,000 shots.

The Amazon spokesperson said the company's internal Covid-19 testing sites could double as vaccination hubs. There are currently more than 650 across the company, the spokesperson said, with the ability to test up to 50,000 employees per day.

Some critics stressed any federal government arrangement with Amazon would need to be carefully vetted — and in the absence of details, some saw potential landmines. Tech watchdogs caution that Amazon’s offer to help comes just two months after it launched an online pharmacy after years of speculation it was eyeing that market.

Michelle Kuppersmith, executive director of Campaign for Accountability, a corporate watchdog group, said she’s concerned about how Amazon would use information from a vaccination effort.

“Amazon is a company that has already amassed an unparalleled amount of data on Americans and we have no idea how it would treat the data gleaned through vaccine distribution,” she said.

Some Amazon critics said they viewed the company’s offer to Biden as an attempt to shore up Washington support while the company and the tech industry overall face growing scrutiny of their business practices, including their use of user data.

“This is Amazon’s attempt to curry favor with Democrats and push the idea that its outsized power is something we should embrace,” said Stacy Mitchell, co-director of the Institute for Local Self-Reliance advocacy group for sustainable community development, who’s been tracking vaccine distribution efforts on the local level.

Other critics are skeptical that Amazon’s offer will amount to much.

“This is a governmental function,” said Alex Harman of the consumer advocacy group Public Citizen. “It might require partnerships here and there, it might entail commandeering of private resources occasionally, but the actual doing of logistics, and figuring out logistics, that’s what government is for.”