Darren Burns at the 2007 Ulster GP with son Nicholas

Lisburn motorcycle racer Darren Burns has decided to withdraw from the Ulster Grand Prix races at Dundrod due to "unforeseen circumstances".

Burns had been expected to return to racing after suffering serious injuries in the accident which cost Robert Dunlop his life at the North West 200.

"My main aim now is to sit out the remainder of the season and get back to full fitness," said Burns.

"Then I'll look ahead to returning next season, starting at Cookstown in 2009."