F1 team principal Frank Williams in hospital

Williams team principal Sir Frank Williams is undergoing treatment on a pressure sore on his back.

Williams - who is 72 - has been tetraplegic since a road accident in 1986, is currently at Stoke Mandeville Hospital in England, with the team saying he is responding well after routine treatment. A team spokeswoman told Reuters Williams "is likely to be there for at least a couple of weeks".

Deputy team principal Claire Williams - Sir Frank's daughter - is missing this weekend's United States Grand Prix in Austin to be with her father, but is due to return in time for the Brazilian Grand Prix.

"She wanted to stay there to make sure he's responding well, which he is," the Williams spokeswoman added.

Williams currently sits third in the constructors' championship ahead of Ferrari with three races remaining in the 2014 season.