Behind a tightly packed top four, all within 29 seconds, Landa sits sixth overall at 1-17 behind Froome.
"If I don’t hurt Froome, I would love make the podium. I feel good and I would like to do it, but I cannot do it at his expense," Landa said. "More than a lieutenant, I can be a key player to stop the rivals."
In 2015, Froome won the Tour de France with two Movistar riders - Nairo Quintana and Alejandro Valverde - on the podium with him. In 2012, Froome stood second alongside winner and team-mate Bradley Wiggins.
Landa has also been in a similar situation before. In 2015, he positioned himself to lead team Astana to the Giro d'Italia win when Fabio Aru suffered early in the race. Aru rebounded and Landa helped him, they finished second and third respectively, behind winner Alberto Contador.
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"The situation is similar [to Wiggins and Froome in 2012] , but you have to take into account that in this Tour, face to face, Froome would win because he will have a good time trial on the penultimate day. We are partners, not rivals," said Landa.
"Yes, the truth is that it reminds me [of Astana]. I've already lived through this situation. But now we are playing to win the Tour, not to be second."
The 27-year-old Basque ride is set to transfer to Movistar in 2018. The deal has been inked, reportedly, but nothing can be announced until August 1.
Landa would not confirm his future team, but said that he wants to be the leader wherever he goes.
"I do not know if my goal will be the Tour de France. The Tour and Giro are different races, different rivals," he said.
"I'll see what my body will allow. The Tour's route suits me better than the Giro. I know, though, it is not the same to come in as a helper or to come in and win."
Some have speculated that Landa is positioning himself to lead the Sky team if Froome falters. On the steep slopes to Peyragudes, he moved ahead while Froome lost 22 seconds. It raised questions about his role and Froome's form.
"In 2016, he was more superior, but he had more terrain for him than he does this year,” Landa continued. “This time the initial time trial was short for him and in Peyragudes, did not have his best day. He's is not much above the others, but he's OK."
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