London - Geraint Thomas has confirmed he will miss the Giro d'Italia to be "in the best shape possible" for the defence of his Tour de France crown.
Last year Thomas, 32, followed in the footsteps of Team Sky team-mate Chris Froome and Bradley Wiggins, becoming the third Briton to win the Tour.
"The Giro feels like unfinished business and I wanted to think about that," Thomas was quoted as saying by the BBC.
"Maybe I'll race it next year but this year has always been about the Tour," added the Welshman, who was forced to withdraw injured from the 2017 Giro.
Last month Thomas, who began his season in the Tour of Valencia on Wednesday, said the Tour de France was his key objective for 2019.
"The main goal for me will be to go back to the Tour de France for the best result I can," he said.
"Maybe if I hadn't have won the Tour in 2018 I might have looked at a Giro/Vuelta programme but, having won the Tour, I'll have the number one on my back and it would be sad not to go back, and not to go back at 100 percent as well."
Team Sky announced last month that Froome, 33, who in 2017 achieved the Tour and Vuelta double, would not be defending his Giro title as he aims for a fifth Tour de France title.
Team Sky's future was thrown into doubt in December after British media company Sky announced it was ending a partnership that has delivered six Tour de France titles in the past seven years.