Staff at accountants Grant Thornton have added new members to their team for the rescheduled OX5 Run in aid of Oxford Children's Hospital.

The OX5 Run at Blenheim Palace, in Woodstock, was due to go ahead on Sunday, April 6, but heavy snowfall overnight led to the postponement of the race.

Now the race has been rescheduled for Sunday, June 1, and organisers are hoping hundreds of new entries will be added to the total of about 500 runners who have signed up so far.

Botley-based finance firm Grant Thornton is now challenging rival firms to enter teams in the race to challenge for the OX5 Cup, which is awarded to the team with the lowest aggregate time of its top five finishers.

Grant Thornton's team, called the Tax Tornados, won the cup in 2006, and they are hoping to win it back from last year's victors, Newsquest Oxfordshire, which publishes the Oxford Mail and Oxford Times.

Mark Fieldsend, the team captain at Grant Thornton, said: "More time to raise sponsorship, and the opportunity to get more people involved, can only be a good thing.

"We are committed to raising funds for local charities and the Oxford Children's Hospital is a fantastic cause.

"We had about 20 staff signed up for the April race and the warmer weather and extra time to train has seen this number increase to 30, representing 25 per cent of our staff."

Grant Thornton is no stranger to fundraising, and last month the firm entered two teams in the annual Rotary Club of Banbury Dragon Boat Challenge at Broughton Castle, raising money for Banbury Young Homeless Project in the process.

Mr Fieldsend added: "Banbury falls within our patch so we were keen to take part from that perspective, but we were also flying the flag for the Oxford business community.

"I'd like to say that it served as a form of extra training for the OX5 Run but it was more arms than legs.

"A couple of the big guns were unavailable for the April date, but they should be present on June 1 so it could be a very close contest.

"Plus there is always the chance that the Oxford Mail team will have peaked too early.

"It would be great to be able to take on teams from other Oxford businesses as well, so hopefully many more will sign up between now and race day."

The children's hospital, on the site of the John Radcliffe, is a charity close to Grant Thornton since Kaye Platt, the wife of tax partner Chris Mundy, is a consultant paediatric radiologist there.

Last year, Grant Thornton raised more than £1,000 for the hospital, which treats 65,000 patients a year.

Susannah Maxa, a spokesman for Chox, said: "This is an ideal event for corporate team building while supporting the local community and it clearly looks as if they need some competition in trying to regain that title."

So far, community groups and businesses have raised £13.8m towards a £15m target, half the £30m cost of the hospital, which is part of the new £130m West Wing, which opened over a year ago.