White House Chief of Staff William Daley will step down from his post at the end of the month, according to a senior administration official.

Daley will be replaced by Jack Lew, head of the Office of Management and Budget.

Daley submitted a letter of resignation to Obama last week.

“I have been honored to be a small part of your administration,” Daley wrote to the president in a letter obtained by the Chicago Tribune. “It’s time for me to go back to the city I love.”

Daley’s departure comes two months after the White House announced that Pete Rouse, the president’s senior adviser, would be taking over the daily operational duties.

Daley has had a turbulent tenure at the White House, where he has reportedly clashed with other officials.

Daley has been President Obama’s chief of staff for a little more than a year. He replaced Rahm Emanuel, who left the White House and eventually was elected Chicago’s major.

(Source: The Hill)