Senate President Emil Jones Jr.’s office issued a news release Monday afternoon announcing his decision to retire when his current Senate term ends in mid-January. He didn’t say why he is stepping down.

“I want to thank the many people throughout the years who have honored me by sending me to Springfield to represent them, as well as the members of the Democratic Caucus who have elected me their leader for the past 15 years,” Jones said in the release. “This has been a great privilege to work on behalf of the people of Illinois for over 35 years.”

Jones, 72, has been Senate president since 2003. From 1993 until the time he became Senate president, he was Senate minority leader. Republicans controlled the chamber during those years, and they held the presidency.

Jones served in the House of Representatives from 1973 to 1983.

In a statement issued by his office, Gov. Rod Blagojevich called the Senate president “a man with a big heart and a man of action.”

“Emil Jones used his position as Senate President to give those without a voice better health care, better funded schools and increases in the minimum wage,” Blagojevich said. “He is a true champion of the people.”

A Blagojevich spokesman declined to respond to a question about how Jones’ departure might affect the governor’s relationship with the legislature.