Lily Allen spent a few years being "cross" with Sir Elton John because he didn't respond to her letter

Speaking on her 'Miss Me?' podcast, she explained to co-host Miquita Oliver: "Over the next few years as my life began to spiral out of control, I held much resentment for the fact that I'd made myself very vulnerable in this letter and told him all about my sobriety.

"He's a sober person so I thought he would have responded to this letter. I was quite cross with him for a few years. I thought it was mean of him."

But it was only when the 'Smile' hitmaker - who now lives in Brooklyn with her husband David Harbour - was unpacking boxes after making the move from London that she discovered that she had never even sent the letter to begin with.

She said: "Then, when I moved here to America, I was unpacking and I found the letter.

"I hadn't sent it. I'd been harbouring all of this Elton resentment."

The 'Not Fair' singer - who has daughters Ethen, 12, and Marnie, 10, with ex-husband Sam Cooper - previously revealed that she decided to leave London for the US partly because of how she wanted her children to be able to grow up in the more "encouraging environment" that she believes the USA to be.

She said: "I think that one of the reasons that I moved here (America) is because I feel like it's a much more encouraging environment in which my children can thrive.

"An example of that would be when I decided to do a play ['2:22 A Ghost Story'] even though I'd never acted before, and certainly didn't have any experience in the theatre