British WorldTour team will be backing Egan Bernal in the delayed 2020 Tour, after the Colombian became the youngest winner of the yellow jersey last season.
Thomas, winner of the Tour in 2018, will instead be given leadership at the Giro d’Italia in October while four-time Tour champion Froome will race the Vuelta a España.
Bernal said: “It’s a bit strange to not have Gee [Thomas] and Froomey in the Tour but I’m excited to see what Gee will do in the Giro d’Italia. It’s a really good Giro for him with the three time trials. So I think he can gain some time there and try to defend in the big mountains.
“Also in the Vuelta who knows, maybe I can go there and try to help Froomey. Now for sure I need to focus on the Tour. After the Tour I have no plans yet.”
Bernal will be supported by reigning Giro d’Italia champion Richard Carapaz and Pavel Sivakov in his bid to defend the yellow jersey.
The 23-year-old added: “It’s really exciting to have this team around me in this Tour de France. I think we are a young team with Pavel and Richard.
“We will enjoy it. We have a young team but with the experience of other riders like Kwiato [Michał Kwiatkowski], Luke Rowe and Jonathan Castroviejo I think it’s a good balance.
“I’m really happy to be in the tour team. I just want to go there and do my best for them and for the team.”
Thomas, who finished second behind Bernal in Paris last year, last raced the Giro d’Italia in 2017 when he was forced to abandon after a crash on stage nine.
On his return to Italy, Thomas said: “In 2017 I was in great shape. I was in a similar form to what I was in 2018 when I won the Tour.
“The Giro ended badly that year with a crash and it’s something I’ve always wanted to go back to. I enjoy the racing there. I’ve always loved Italy, the roads and the fans and the food obviously. I’m looking forward to going back.”
While Thomas has previously said he wants to target the Giro again one day, for 2020 he was determined to race the Tour in the hopes of repeating his 2018 victory.