The biggest dog in Britain has been put on a crash diet after vets decided he was too heavy to undergo a life-saving operation. Samson, who weighs in at just under 20 stone and stands 6ft 6in tall on his hind legs, is suffering after rupturing a cruciate ligament in his left hind leg. His owners Ray and Julie Woods, from Wyberton, Lincolnshire, have been forced to put the 1,400 pound surgery he needs on hold until he has lost weight. Vets warned that he is so heavy that if he has the operation now he will not recover properly, and may never be able to walk again. Mrs Woods, 54, Wyberton, Lincolnshire, said: "The operation is on hold for the time being. But we have been told that there is a 90 per cent chance that he will need it in the next six months. "If the ligament gets worse and goes completely he will need the surgery. But we are frightened if he has the operation he may not be able to get up again. "It is a terrible thought because if he doesn't get up again, he may have to be put down." The four-year-old Great Dane-Newfoundland stands just an inch shorter than England striker Peter Crouch when on his hind legs. It costs 30 a week to keep Samson fed, and he also eats a turkey leg every day. Mrs Woods now hopes to get Samson fit with a regime of dieting, physiotherapy and hydrotherapy. She said: "Samson has put on four stone since we got him - he is big but he is not a fat dog.  "It is important with big dogs that you keep their weight down. "We feed him on dry food just twice a day, but he also has a turkey leg."               " Telegraph