PRIME Minister David Cameron is urging people to sign up for the OX5 Run, on the eve of its one-month countdown.

The five-mile fun run at Blenheim Palace, Woodstock, takes place on March 10.

Four years ago, the Witney MP was the official starter, and joined other runners to raise money for the Oxford Children’s Hospital.

Mr Cameron is unable to take part again this year because of commitments, but is urging people to join the run to help raise more money for the Headington hospital.

He said: “The cold start and hills are nothing compared to some of the challenges young patients face each day at the Oxford Children’s Hospital.

“I hope everyone will get stuck in and lend their wholehearted support to this brilliant campaign.

“Having taken part in this fantastic event myself in 2009, I am urging the Oxfordshire business community to get involved and enter as many teams as possible.”

Mr Cameron’s son Ivan, who had cerebral palsy and severe epilepsy, died in 2009 at the age of six.

Last year’s OX5 Run netted £60,000 for the children’s hospital.

The money is helping to pay for a new eye scanner for babies and children, a machine to measure lung function in children more easily and a portable ventilator for sick children being transported between intensive care, theatres and the X-ray department.

The hospital’s head of community fundraising Graham Brogden said: “We are delighted to have the support of the Prime Minister for this very special event. Mr Cameron knows first-hand how much fun taking part in the OX5 is, having completed the five miles himself in 2009.

“We also hope the business community will take the challenge and enter a team, helping us to make this our most successful fun run ever.”

So far 600 people have entered the race, including more than 50 teams.

This year marks the 11th year of the OX5 Run, which is sponsored by Oxford-based recruitment firm Allen Associates and organised by the Oxford Mail.

To take part, call 01865 743444 or go to oxford mail.co.uk/news/ox5run