Mark Cavendish is to take a complete break from cycling in order to recover from illness.
Cavendish has been diagnosed with Epstein-Barr virus and medical examinations revealed that the cyclist has unknowingly raced with the illness over recent months.
In a joint statement released with the Briton's team, Team Dimension Data, Cavendish revealed that the virus has affected his performance this season and will now tale a "period of total rest" in order to recover.
"This season I've not felt physically myself," Cavendish, 33, said. "Despite showing good numbers on the bike I have felt that there's been something not right.
"Given this and on the back of these medical results, I'm glad to now finally have some clarity as to why I haven't been able to perform at my optimum level during this time.
"Having received expert medical advice as a result of the findings I've been advised to take a period of total rest in order to fully recover.
"I'm now looking forward to taking the time necessary in order to get back to 100 percent fitness before then returning to racing again at peak physical condition."
Cavendish was eliminated from this year's Tour de France after being left behind in the mountains and failing to make the time cut during Stage 11.
The former world road race champion also withdrew from the inaugural European Championships on medical advice earlier this month.
Cavendish was previously diagnosed with EBV in April 2017 but returned to action in the Tour of Slovenia that June.