Top EU bosses say the UK’s impending exit will force a change of tone of the budgetary debate, with calls to shake-up and simplify funding.
And some claim European chiefs could try to sneak in a new EU tax to siphon off resources that should go straight to member governments.
In 1984, Margaret Thatcher agreed a UK-rebate, which saw London get back roughly two-thirds of its net contribution to the bloc.
Other EU member were then forced to pay in more, and in turn a “rebate on the rebate” was agreed – capping the contributions of Germany, the Netherlands, Sweden and Austria.
But Brexit is likely to bring an end to all that.
So the bloc could be left with no choice but to enforce a shake-up of the rules and find new ways of bringing in some cash.
In the new report, Mr Monti’s 10-member group denounced a “long neglect of how the EU is financed”.
But the options suggested – including an electricity tax, a carbon levy, a motor fuel levy or a share of taxes on corporate income – could kick up some complaints from member states.
Both Germany and the Netherlands have already voiced their opposition to any additional revenues beyond customs and the VAT slice to fund the EU, arguing such a move would breach their constitutions.
The study will be presented to a panel of EU finance ministers on January 27.