Wiggins was the first Briton to win the world's most famous cycle race in 2012 but team leader Froome said a place even as a super domestique rider was by no means certain just over a month before the endurance classic gets underway in Leeds on July 5.
"Talking about a Plan B, that's a decision the team needs to come to, and Bradley has been talking about playing a support role, not being our Plan B as such," fellow Briton Froome told the Daily Mirror newspaper.
"Richie is looking pretty good at the moment and has the potential to be riding for a place on the podium.
"As far as Bradley is concerned, the final nine riders selected to start the race in Yorkshire is a hot topic.
"That's going to come down to what is best for the team, who is best for each role and the team dynamics."
Wiggins announced his intention of racing in the Tour de France after an impressive victory in the Tour of California last month.
Already tense relations between the two riders were likely to have been further strained after Froome's recently released book revealed they had fallen out in 2012.
"I would have been criticised a lot for not covering that topic in my autobiography," Froome told the paper.
"Until now people have only seen Bradley's version of events, so it was important for me to put out what I felt happened. But these issues have been put to bed and are in the past now."
The 29-year-old Porte played a key support role in Froome's victory last year, acting as his main climbing deputy in the major mountain stages on his way to a 19th place finish.
- Sports & Recreation