Robbie Williams has started smoking again.

The 42-year-old singer ditched his naughty habit four years ago when daughter Teddy was born but recently turned to the cigarettes again after undergoing a strict diet regime.

After piling on the pounds when he first stopped smoking, Robbie revealed: ''I went on this pretty hardcore diet. You woke up and had a boiled egg, then nothing for five hours, then had vegetable broth, then steamed veg, then nothing until the next day. After five days of that, first off, I was really f**king emotional, because you've got nothing, your body's starving. And the second thing is, you just needed something to suppress your appetite, so this started again.''

However, his wife Ayda Field hates him smoking, so the 'Angels' singer tried to hide it from her.

He told The Guardian newspaper: ''I tried to hide it from my wife for five weeks. What I'd do, at night I'd hide my mouthwash and hand sanitiser in a safe place, then wake up an hour before she got up, climb out of the window, take my top off, so as not to smell of anything, then smoke, hand sanitiser and mouthwash, top back on, shoes off so as not to wake her up, climb back in the window.''

However, his secret was soon discovered but has vowed to give up again before going on tour next year.

Robbie - who admitted to replacing nicotine with sugar - said: ''You know the first smoke in the morning, when it makes you disorientated, but it's quite beautiful? There were a few mornings when I couldn't get back in the house for at least five minutes because I'd be so out of my fucking head. And then at one point, I mouthwashed myself with the hand sanitiser. Anyway, I've started smoking again. January's the cut-off point, then I go on tour and I hope I don't look like Elvis before he died. And, you know, when that fire goes out, hopefully the next one isn't sugar. Or anything that will put my marriage in jeopardy.''