The 19 year-old has arrived for an undisclosed fee but chairman Darragh MacAnthony confirmed it is 'the biggest amount spent on one player this summer'.
He was also attracting attention from two Championship outfits and fellow League One club Huddersfield.
Posh boss Darren Ferguson said: "This goes along with our policy of signing young, hungry players. He has real potential."
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The full article contains 110 words and appears in Peterborough ET newspaper.