The 34-year-old, said she was still "90 percent" confident she could be fit but would only go if she felt competitive.

"It's not good news and not the news I wanted to hear, but I will give myself every chance," said Radcliffe, who has been on crutches with what was originally thought to be a hip injury.

Radcliffe said it was only when she eventually had a bone scan after two MRI scans on her hip that it was discovered she had an "atypical femural compression" rather than a hip injury.

"The bottom line is it's not ideal and some specialists have said with the training I need to put in it would be impossible," she said. "I will give myself every chance but I won't run through pain and I won't go if I feel I can't be competitive.