Chelsea, Manchester United and Liverpool have been criticised for carrying high levels of debt by a Parliamentary inquiry.

Following a year-long investigation into “English Football and its Governance”, the All Party Parliamentary Football Group has released a report urging tougher regulation of English football, and called for the game's rulers to reduce the “ludicrous levels of borrowing” in the Premier League.

The Premier League clubs are estimated to have a collective debt of about £2.5billion, with Football Association chief Lord Triesman last October attacking the spending policy of England's elite clubs.

The top three in the Premier League carry the biggest debts, with United's parent company having liabilities of £649m while Chelsea's debt to owner Roman Abramovich stands at £339m.

“The financial world has learned a serious lesson in the last year that living by the old adage, if it ain't broke, don't fix it' can lead to catastrophic results,” said backbench Labour MP Alan Keen, who chaired the inquiry.

“There is a real danger that English football could go the same way. Corrective action needs to be taken now to address serious weaknesses in the governance of the game as well as severe financial imbalances.

“Lack of proper governance and financial instability are the two fundamental vulnerabilities to the success that English football has enjoyed.

“Our report includes measures to improve the way the game is run and to combat financial doping' whereby short-term success can be bought at the expense of long-term stability.”

The report supports FIFA president Sepp Blatter's campaign for the introduction of the “six-plus-five” rule, which would place a limit on the number of foreigners in a team.

It also called for a strengthening of the Fit & Proper Persons Test', which determines whether foreign tycoons trying to take control of English clubs.

However, the group has no power to implement its recommendations.