The reason for the collapse of the deal remains unknown with both parties blaming each other.
Scotland Under-21 international Scougall insists the Sky Bet League One club "moved the goalposts" while Posh director of football Barry Fry claims the move failed to materialise due to some of the demands made by the player and his agents.
"Disappointed talks broke down with Peterborough over the question of personal terms and not that I didn't want to move away which was reported," Scougall said via his Twitter account.
"The deal wasn't the right deal for me just now. I'm just looking forward to getting back to full fitness and having a good season with Livingston and helping the team move up the league.
"Just for the people asking....I wasn't asking for too much. In fact everything was in place before Peterborough moved the goalposts."
Scougall's suggestions provoked an angry response from Fry, who said: "We haven't moved the goalposts at all. Every time we thought we had a deal agreed with the player, his representative would ask for something else.
"We have dealt with three different agents in the last five weeks and it made the deal impossible to complete. They were asking for B£30,000 if he won a Scotland cap, they wanted a cut of any future transfer fee and we never do that for players.
"They also wanted to sign a contract before he had a medical and we're talking about a player who hasn't played or trained since July 3."
- Sports & Recreation