BIRMINGHAM, October 6 – Marathon world record-holder Paula Radcliffe has been forced out of Sunday's World Half-Marathon Championships here with tonsilitis, the British athlete announced on Monday."I’m devastated not to be able to compete in Birmingham this weekend," she said. "The world half-marathon is a great opportunity for our athletes to compete in front of a home crowd and I’m disappointed I can’t be part of that.

"It’s very important to me to be able to pull on a GB vest and do my best in a major championship but, unfortunately, having developed tonsilitis over the weekend, I’m now on a course of antibiotics."

Radcliffe has been replaced by first reserve Michelle Ross-Cope.

The 35-year-old had to withdraw from the marathon at this summer’s World Championships because she had failed to recover fully from a foot operation in the spring.

Radcliffe would have been chasing a record fourth victory in Birmingham, having already tasted success in 2000, 2001 and 2003.

She is currently level with Kenya-born Dutchwoman Lornah Kiplagat, champion in each of the last three years but sidelined this year due to a knee injury, while Kenya’s Tegla Loroupe won the race in 1997, 1998 and 1999.

Radcliffe won the marathon at the World Championships in 2005, but could only finish 23rd at the 2008 Olympic Games in Beijing after suffering a stress fracture.