STAMFORD - U.S. Sen. Joe Lieberman publicly announced his retirement in Stamford this afternoon.

Lieberman told a group of about 200 people at the Stamford Marriott that he has decided not to run for re-election when his term ends in 2012. He says it was a tough decision to make, but that he knows it is time to move on.

Many southwestern Connecticut residents say they are sad to see him go after years of fighting to keep jobs in the state and help local union leaders.

At the end of his current term, Lieberman will have served 24 years in the Senate under four presidents and a total of 42 years in elected office.

VIDEO: Sen. Lieberman retirement speechRead his full speech here