NEW YORK - Mayor Bill de Blasio took no questions from reporters after leaving a long anticipated meeting Friday morning with the U.S. Attorney's Office in Midtown.

The mayor arrived in an SUV shortly after 9 a.m. to attend the meeting inside 1177 Sixth Avenue.

He emerged roughly four hours later.

For the past two days, the mayor has been inside in his attorney’s office for hours at a time, presumably preparing for this interview. 

Friday's meeting comes as the U.S. Attorney’s office potentially wraps up a lengthy investigation into the mayor’s fundraising and campaign activities.

De Blasio voluntarily agreed to sit down with federal investigators and he has not requested or been offered immunity to do so. 

His office says the mayor and his aides have always acted appropriately. 

This is de Blasio's second interview with prosecutors; he was interviewed by the Manhattan District Attorney's office in December in relation to a different investigation.

The mayor is also under investigation by the Manhattan District Attorney's office in connection with state senate campaigns he assisted in 2014.

In a statement, City Hall stressed the mayor met with investigators "voluntarily" adding, "We remain confident that at all times the Mayor and his staff acted appropriately and well within the law. We hope our continued cooperation will help bring a swift conclusion to the U.S. Attorney’s review."

From Manhattan, the mayor was back to politics; he was heading to Atlanta to attend the Democratic National Committee's winter meeting.