Amazon.com and Sen. Bernie Sanders (I-Vt.) are sparring over working conditions at Amazon warehouses, after the senator called for legislation that would require large employers to reimburse the government for food stamps, Medicaid and other federal assistance received by their employees.

Amazon on Wednesday published a rare blog post rebutting the senator’s claims that thousands of Amazon employees rely on federal benefits to make ends meet. Those figures are “inaccurate and misleading,” the company said, because they include temporary workers as well as those who choose to work part time.

The Seattle-based tech giant has typically stayed above the political fray, most notably by refraining from responding to President Trump’s repeated Twitter attacks on the online retailer and its founder, Jeffrey P. Bezos. (Bezos owns The Washington Post.)

“While Senator Sanders plays politics and makes misleading accusations, we are expending real money and effort upskilling people,” the company said. “We have been in regular contact with his office and have offered several opportunities for Senator Sanders and his team to tour one of our fulfillment centers (FCs). To date he has still not seen an FC for himself.”

A few hours later, Sanders responded with a press release of his own.

The senator said he had requested to visit an Amazon warehouse in Wisconsin in July, but “unfortunately, Amazon could not accommodate me then.” Sanders added that he is planning to visit a facility in Chester, Va., next month.