Cameron's 'immense void' over son

Ivan, who suffered from cerebral palsy and epilepsy, died in February this year. He was the oldest of Mr Cameron's three children with his wife Samantha.

In an interview with Grazia magazine, Mr Cameron said: "So much of our life was arranged around Ivan, the void is immense."

He added: "But also, you are suddenly able to do things you couldn't do before, like walk across a muddy field perhaps, and you find yourself there quickly and it's like 'oh, here we are' followed by a feeling of guilt because you're having a good time and he's not there."

Asked whether he had plans for more children, the Tory leader said: "I'd certainly like to, but we'll have to wait and see if the stork drops one off."

Mr Cameron also spoke of his respect for his wife, who works as creative director for luxury stationery and leather goods brand Smythson. He said the couple occasionally argued but it was usually over his busy schedule as Mrs Cameron was "very protective of our time together".

He added: "She'd much rather sit at home watching The Wire with a plate of pasta than be at some exciting, flesh-pressing opportunity." And Mr Cameron said his wife "regularly cured" him of speaking a "politicians' language".

He said: "She has a brilliant 10,000 feet view. Because she's busy designing the next hit handbag or whatever, she has an objectivity that is incredibly useful in a politician's life.

"There will be something I've had a long meeting about, juggling thoughts about whether we should do x or y, and later at home she will just say 'well, it's completely obvious that you should do y'.

"She's interested in politics but sometimes politicians have their own language and she cures me of that regularly. She'll say: 'If you put it like that, no-one will have a clue what you're on about."