(WASHINGTON) -- Major retailers have increased the price of at-home COVID-19 tests now that an agreement with the White House to sell them at a fixed price has expired.
In September, Walmart, Kroger and Amazon agreed to sell the two-pack boxes of at-home rapid antigen tests for $14 for three months amid a surge in positive cases with the delta and omicron variants. The agreement has since expired, according to a White House official.
Walmart is now charging $19.88 per box, where available, and Kroger has raised the price to $23.99. The brand is currently unavailable on Amazon's website.
Despite the price hike, the at-home tests remain sold out -- both online and in stores across the country
When asked Wednesday whether the Biden administration is currently in talks with retailers to bring the price of the tests back down, White House press secretary Jen Psaki declined to say.
"I can't give you an update on any conversations," Psaki said.
Instead, she pointed to other steps the administration is taking to make tests more available, including purchasing 500 million tests to distribute to Americans for free and requiring insurance companies to reimburse Americans for the tests starting next week.
The government will begin to receive the tests later this month and will then distribute them free of charge, Psaki told reporters on Tuesday, adding that she does not "have an update" on how long it will take to send out all 500 million tests and whether the distribution will occur over a certain period of time.
ABC News' Mike Hernandez and Elliot Rubin contributed to this report.