Geraint Thomas says he is "all OK" after crashing in the Tour de Suisse cycling race and is optimistic about defending his Tour de France title next month.

The British rider says in a Twitter post he hit his head and needed stitches above his eye after hitting the road with about 30 kilometers (18 miles) left in the fourth stage of the nine-day race in Switzerland.

Thomas, who was forced to withdraw from the race, says it "just means I'll need some big training rides next week" as he prepares for the Tour de France, which starts July 6.

Thomas rides for Team INEOS, who lost four-time Tour champion Chris Froome to a season-ending accident last week in the Criterium du Dauphine.