Downing Street moved to clear up speculation over Brown’s health by insisting there had been no deterioration in his vision following rumours that he was going blind.

Brown, 58, who lost the use of his left eye in a childhood sporting accident, had tests over the summer and a follow-up check-up on Friday showed his functioning eye had not worsened.

"This summer Mr Brown had his annual eye check-up which was fine. Later he had his retina checked," a Downing Street spokesman said.

"After examinations surgeons found that the retina had two minor tears. However, as there has been no further deterioration, and no change in his eyesight, they decided against further operations.

"Yesterday Mr Brown visited Moorfields Hospital as part of regular checks on his eyes and this check was also fine."

Brown was forced in a US TV interview last month to deny that was losing his remaining eyesight, saying: "My sight is not at all deteriorating."

Interviewed by BBC TV days later he fended off allegations that he was dependent on prescription drugs, and said that although his eyesight was a "problem" it was not failing.

AFP/Expatica