The Trump administration fired prominent U.S. attorney Preet Bharara Saturday, after he refused to step down as requested Friday in a Department of Justice sweep of all remaining Obama-era attorneys.

Bharara was blindsided by the letter asking for his resignation Friday, because of explicit assurances from both President Donald Trump and Attorney General Jeff Sessions that he would be asked to stay on through the transition, reports CNN. He did not send in his letter Friday, and told associates he had no plans to do so over the weekend, sources told The New York Times.

The refusal prompted the administration to fire him outright.

“I did not resign,” Bharara tweeted Saturday afternoon. “Moments ago I was fired. Being the US Attorney in SDNY will forever be the greatest honor of my professional life.”

Bharara has a reputation for aggressively and successfully going after banks and Wall Street insiders, and is finishing up an investigation into New York Mayor Bill de Blasio, as well as reportedly continuing an investigation into the way Fox News handled settlements of sexual harassment claims by some of its employees. He was also about to start trials of two former aides to New York Gov. Andrew Cuomo.

[dcquiz] The Justice Department’s move to clear out attorneys from the former presidency has become custom in recent transitions, so it’s not particularly surprising. Former Presidents Ronald Reagan and Bill Clinton each dismissed about 90 attorneys in the early months of their presidency. Many of the Obama-era attorneys have already resigned, but Sessions asked the remaining 46 appointed prosecutors to leave their post in the letter Friday, including Bharara.

“Been in the works for awhile,” a senior administration official told Politico, referring to the letter sent Friday. “Decided to pull the trigger today. We were always planning for it on about Day 50.”

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