Nicole Cooke, the 2008 Olympic road race champion, has retired from cycling with immediate effect.
The 29-year-old, who also won the world road race title in 2008, becoming the first person to win both events in the same year, announced her decision in central London on Monday.
Cooke said on the Cycling Weekly website: "I am very happy with my career. I have many, many happy memories over what has been my life's work since I was 12.
"I have won every race and more that I dreamed I could win."
British Cycling president Brian Cookson paid tribute to Cooke, saying: "Nicole has enjoyed unparalleled success during her 13-year career.
"One of British Cycling's finest moments in recent years was her truly memorable win in the women's Olympic road race in Beijing.
"There is no doubt that Nicole has been a pioneering force in women's cycling for the past decade.
"She inspired many youngsters to take up our sport. British Cycling owes a huge debt of gratitude to her and wish her all the best."