German sprinter Marcel Kittel is to take a break from cycling, saying he is "exhausted" and unable to compete at the highest level at the present time.
The 30-year-old, who has won 14 stages of the Tour de France, has had his contract with the Katusha-Alpecin team cancelled by mutual consent.
"In the last two months I have had the feeling of being exhausted," Kittel said in a statement.
"At this moment, I am not able to train and race at the highest level. For this reason, I have decided to take a break and take time for myself, think about my goals and make a plan for my future."
Kittel, who emerged as a key rival for Mark Cavendish on the 2013 Tour with four stage wins and wore the yellow jersey after victory on the opening stage in Harrogate 12 months later, has struggled for form and results over the past year.
His win at the Trofeo Palma in February was his first victory since he took two stages of Tirreno-Adriatico last March. His last Tour stage win came in 2017.
Kittel had been due to compete at the Tour de Yorkshire last week but withdrew on the eve of the race.
Katusha-Alpecin's general manager Jose Azevedo said: "We understand the situation in which Marcel is and we fully support him in this difficult time.
"All the team members will continue supporting Marcel in the future and we hope that he will soon get back to racing as the champion he is."