Berlin  - World record holder Paula Radcliffe of Britain won't run in Sunday's marathon at the world championships because she doesn't feel fit enough to charge for the gold medal.

The British federation UK Athletics announced the news on Thursday, five days after Radcliffe had ran her first race in 10 months after foot surgery, winning a half marathon in New York.

"I am devastated that I wasn't able to be ready in time to represent Britain here in Berlin, especially having got so close in such a short time frame," she said.

"However, after having the surgery to successfully put the years of injury behind me it is very important to me that I come back to racing often and winning at 100 per cent and continue strongly and successfully through to (the Olympics in) London 2012."

British head coach Charles van Commenee said: "To lose an athlete of Paula's calibre is disappointing to say the least. She won the world championships in 2005 and a fit Paula would clearly be in contention to regain that title, but she has taken that difficult decision and we have to respect that."

Radcliffe, 35, holds the world record over the 42.195-kilometres distance with 2:15:25 at the 2003 London Marathon.

However, she has always struggled at championships, with a 2005 worlds gold her only title. She has a 10,000m silver as well from 1999.

Radcliffe did not compete at the 2008 worlds and had to settle for 23rd in the Beijing Olympics marathon last year over injury problems.

"Running in New York this weekend was a necessary part of the process to ascertain my race fitness and after speaking with my coaching and medical team, I knew I was sadly just not quite ready," she said. (dpa)