Paula Radcliffe has been forced to pull out of Sunday's World Half-Marathon Championships in Birmingham due to illness.

The three times former champion and marathon world record holder is suffering from tonsillitis.

"I'm devastated not to be able to compete in Birmingham," said Radcliffe, who also missed the recent World Athletics Championships due to injury.

The 35-year-old added: "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 for me to be able to pull of a GB vest and do my best in a major championship."

Radcliffe has now set her sights on competing at next month's New York Marathon.