Labour leader and Doncaster North MP Ed Miliband has had a successful operation to deal with the condition sleep apnoea, his office said.
The hour-long NHS operation was performed at the Royal National Throat, Nose and Ear Hospital in central London.
Mr Miliband revealed in April he suffered from sleep apnoea, which interrupts breathing during sleep, made worse by a deviated septum in his nose.
Sources close to the Labour leader dismissed media speculation that he was hoping the operation would make his voice less nasal.
One source who spoke to him after the op said he sounded ‘exactly the same’.
A spokeswoman for the Labour leader said: “Ed Miliband had an operation this morning to correct a deviated septum in order to help with his sleep apnoea.
“The hour-long operation was done with the National Health Service and was performed at the Royal National Throat, Nose and Ear Hospital in central London.
“He is now recovering for a few days before going on holiday with his family.”
Obstructive sleep apnoea is a respiratory condition in which the throat repeatedly narrows or closes during sleep, stopping air getting into the lungs and momentarily waking the person up.
Symptoms include heavy snoring and day-time fatigue. Celebrity sufferers include comedian Billy Connolly, writer Christopher Hitchens and actor William Shatner.
A Labour source said that the operation to correct Mr Miliband’s deviated septum was ‘absolutely not’ intended to alter his voice.
He added: “I’ve spoken to him since the operation and his voice sounds exactly the same. It wasn’t done in terms of changing his voice at all.”