Unions representing thousands of federal employees are challenging an email that requires workers to list five accomplishments from the past week.

In a letter to Charles Ezell, acting director of the Office of Personnel, Everett Kelley, national president of the American Federation of Government Employees wrote, “The email fails to identify any legal authority permitting OPM to demand the requested information. OPM’s actions conflict with laws delegating the authority for the management of federal employees to their respective agencies and do not comport with OPM’s own regulations and guidance.”

Elon Musk, who is not part of OPM, previewed the letter on Saturday on X, noting that failure to reply would be "taken as a resignation."

Along with requesting an apology on behalf of its union members, Kelley criticized Musk’s influence.

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“By allowing the unelected and unhinged Elon Musk to dictate OPM’s actions, you have demonstrated a lack of regard for the integrity of federal employees and their critical work,” Kelley wrote in his letter to OPM’s acting director.

AFGE and other unions have also sued, challenging the legality of the email. The union has asked a judge to declare OPM’s actions illegal. A hearing is scheduled for Thursday.

Meanwhile, leaders at some agencies, including the FBI and the Department of Defense have told staff members that they do not need to reply to the OPM email.

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However, President Donald Trump expressed support for the effort.

"I thought it was great because we have people that don't show up to work and nobody even knows if they work for the government. So by asking the question, 'Tell us what you did this week,' what he's doing is saying, 'Are you actually working?' And then if you don't answer, like, you're sort of semi-fired or you're fired because a lot of people are not answering because they don't even exist. They're trying to — that's how badly various parts of our government were run by and especially by this last group," Trump said in the Oval Office on Monday.