Radcliffe is targeting a record-equalling fourth London win

The 34-year-old set the world record of two hours 15 minutes 25 seconds over the London course in 2003.

"I love running in front of my home crowd. I know winning a fourth time will give me just the boost I need before the Olympic Games," she said.

But Radcliffe has opted out of March's World Cross-Country Championships.

It had been hoped that the two-times champion would represent the Great Britain team competing at the event in Edinburgh.

But Radcliffe's manager and husband Gary Lough confirmed on Tuesday that will not be the case.

Radcliffe gave birth to daughter Isla last January but raced straight back to form, winning the New York title; her first marathon in more than two years.

The London field is always competitive, but that's what I need to be at my best in Beijing Paula Radcliffe

The Bedford runner held off Gete Wami in a thrilling sprint to victory and will again go head-to-head with the Ethiopian in London.

Berhane Adere, Romania's Constantina Tomescu-Dita and Australia's Benita Johnson complete a testing line-up.

Radcliffe said: "The London field is always competitive, but that's what I need to be at my best in Beijing."

606: DEBATE Can Paula win on her return?

London Marathon race director David Bedford was delighted to welcome Radcliffe back to the race line-up for the first time since 2005.

"No doubt all eyes will be on Paula as she goes for her fourth victory," said Bedford.

"But the women's race will be as tough as ever, and Gete will have something to prove after losing to Paula in New York."

A fourth victory in London for Radcliffe, who took gold at the worlds championships in 2005, would see her match Norwegian Ingrid Kristiansen's record achievement.

But the Briton's main aim for 2008 is to make amends for her Olympic nightmare in Athens four years ago, when she failed to finish the marathon in gruelling conditions.

Heat, humidity and pollution will make winning Olympic gold even more difficult in China and Radcliffe is continuing her warm-weather training in South Africa before making her final preparations at altitude in Flagstaff, Arizona.