Preet Bharara, the Manhattan federal prosecutor who was asked by President Trump to remain in his post shortly after the election, was fired on Saturday after he refused an order to submit his resignation.
Mr. Bharara’s dismissal capped an extraordinary showdown in which a political appointee who was named by Mr. Trump’s predecessor, President Barack Obama, declined an order to submit a resignation.
“I did not resign. Moments ago I was fired. Being the US Attorney in SDNY will forever be the greatest honor of my professional life,” Mr. Bharara wrote on his personal Twitter feed, which he set up in the last two weeks.
Mr. Bharara was among 46 holdover Obama appointees who were called by the acting deputy attorney general on Friday and told to immediately submit resignations and plan to clear out of their offices. But Mr. Bharara, who was called to Trump Tower for a meeting with the incoming president in late November 2016, declined to do so.
Mr. Bharara said he was asked by Mr. Trump to remain in his current post at the meeting. Mr. Bharara met with Mr. Trump at Trump Tower, and then addressed reporters afterward.
Before the firing, one of New York’s top elected Republicans voiced support for Mr. Bharara on Saturday.
“Good for Preet, he is doing the job he was appointed to do!” Assemblyman Brian M. Kolb, the State Assembly minority leader, wrote on Twitter.
Assemblyman Steven F. McLaughlin, a Republican who was fond of calling for draining the swamp in Albany long before Mr. Trump embraced that expression, had urged Mr. Trump and Attorney General Jeff Sessions to reconsider on Friday.
“Big mistake,” he wrote on Twitter.
The Southern District of New York, which Mr. Bharara has overseen since 2009, encompasses Manhattan, Mr. Trump’s home before he was elected president, as well as the Bronx, Westchester, and other counties north of New York City.
Mr. Trump last weekend accused former President Barack Obama of wiretapping Trump Tower in Manhattan, an allegation he has yet to back up.
But federal investigators have been examining whether there was a connection between Russian officials and the Trump campaign. Intelligence officials believe that the hacking of emails belonging to the Democratic National Committee and campaign officials for Hillary Clinton was orchestrated by the Kremlin.