But the TV talent judge encouraged the youngsters to touch the sky, by delivering an inspirational message: "You can do it".

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John, who starred as a judge on BBC2's The Speaker, came to Leeds to give youngsters a pep-talk on achieving their dreams.

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The athlete-turned-psychologist, who was the first English player to play in the National Basketball Association in America, spoke to the pupils about their plans for the future – and encouraged them to reach for the stars.

He said: "Speaking to children is definitely the scariest thing you can do. It's much scarier than basketball, because you have to engage them.
"The kids at this school have got some pretty tough goals but they're being taught to believe in themselves, which is great.

"They can achieve anything they want if they put their minds to it and work hard. So the simple message is, you can do it."

Pupils at Bramley St Peter's welcomed John to launch their weekly "ethos statement", which this week reads "I value my achievements".

They spoke to John about their plans for the future, with some pupils wanting to become footballers, firefighters and cowboys.

And the basketball champ, who towered above the pupils, told them they could achieve their goals – with a bit of help from their mum.

He said: "I only started playing basketball when I was 17, which is very late. I was chubby as a child and people thought it was impossible.

"But I was lucky because my mum said I could do it. And I believed my mum."

Since retiring from basketball, John has forged a career as a psychologist and speaker and travels globally to talk about a range of topics.

Bramley St Peter's headteacher Cath Harbrow said: "We talk a lot about achievements and we encourage the pupils to set themselves targets.

"John is a very inspirational person."