LONDON — For more than a year, an asthmatic 74-year-old grandfather and former oil executive has sat in a prison in Jidda, Saudi Arabia, accused of violating the country’s strict prohibition on alcohol after the authorities found bottles of homemade wine in his car.

The case of the former executive, Karl Andree, a Briton who has lived in Saudi Arabia for 25 years and is a cancer survivor, has now become a matter of geopolitical controversy amid an outcry over the sentence he faces: 350 lashes, a punishment that his family says could kill him.

The British government said Tuesday that it was canceling a program to train prison officers in Saudi Arabia and that Prime Minister David Cameron would make a personal appeal for clemency, as Mr. Andree’s case continued to draw attention on social media.

“We are actively seeking his release as soon as possible,” the Foreign and Commonwealth Office said in a statement. Officials later announced that Mr. Cameron also planned to make a personal request, in writing, for a review of the case.