A Delaware judge sentenced a man who exposed himself to a 10-year-old girl at his workplace twice to don a T-shirt emblazoned with the words: "I am a registered sex offender."

Russell Teeter, 69, admitted to two counts of indecent exposure. He will also face 60 days in jail.

Deputy Attorney General Donald Roberts said he had called for the T-shirt punishment due to concerns that Teeter might expose himself to children again while running the gardening business he runs with his wife.

"This is a unique way to let his customers know that he is a sex offender," Roberts told Reuters.

Roberts said Teeter had a past history of such behavior with at least 10 prior convictions dating back to 1976. He has been diagnosed to being a compulsive exhibitionist.

Teeter, will have 30 days to appeal the sentence. If it pushes through he is required to wear the T-shirt at work for 22 months after his jail sentence.