The climate action group is staging a four-day protest outside Parliament Square from 21 April, but has been in talks with the marathon race director to ensure minimal disruption.
A Just Stop Oil activist also confirmed there are no plans to disrupt the race on Sunday, although they encouraged protesters to attend.
An Extinction Rebellion spokesperson said: “There’s over 200 groups who have joined us for the weekend and everyone is committed not to disrupt the race and our stewards who are responsible for the whole group will facilitate that.
“It’s our intention to facilitate the marathon to take place smoothly.”
Extinction Rebellion said it had been in talks with the London Marathon since November, which the spokesperson described as “a really fruitful conversation about how we can share the space”.
The spokesperson added: “For us, really, it’s just an example of how you can have a mature conversation about how to deal with the crisis, it’s in stark...