The world marathon record holder, who in the last week has been suffering from a chest and throat infection, claims she is still not ready to compete at this level and has pulled out of the country's most popular 10k running event.

"I'm really, really disappointed to have to pull out of the Bupa Great Manchester Run," said the 37-year-old Radcliffe.

"I have missed racing so much and was so looking forward to running in Manchester in such a vibrant event.

"However, frustrated as I am, I know that the main focus for me is next year's Olympic marathon and achieving a qualifying standard later this year.

As an asthmatic I know that bronchitis, especially at altitude, needs to be treated with caution immediately.

"Therefore it is vital to get fully healthy and have a strong comeback race as soon as possible."

It would have been Radcliffe's first competition since the New York City Marathon in November 2009, when she then took time off to concentrate on having a second child.

She gave birth to son Raphael at the end of last September before gradually returning to full time training.

"Obviously we're deeply disappointed that she will not make her first ever appearance in the Bupa Great Manchester Run and of course her comeback race." said Andy Caine, the event's elite athlete's manager.

"But Paula has always insisted, with her primary centred on winning next year's Olympic marathon title, she will not take unnecessary risks in achieving that target.

"We wish her a speedy recovery and I'm sure everyone will look forward to seeing her racing again when fully fit and healthy."

Radcliffe has developed a record of withdrawing from races in the UK in recent years.

She has not raced in the London Marathon since 2005, which she won in 2 hours 17min 42sec, a world's best time in a women's only marathon, due to a combination of injury, illness and pregnancy. 

The Bedford runner also withdrew from the 2009 International Association of Athletics Federations (IAAF) World Half-Marathon Championships in Birmingham because of illness.

She is now due to make her combeack to competition at the Bupa London 10,000 road race on May 30, an event that is due to be held over part of the course proposed for next year's Olympic marathon.


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