I don't want to get bogged down in Brexit politics, but someone should point out that the £100B figure is not something to take seriously.
Firstly, it's not an official figure but rather an estimate by outside observers of the maximum bill the UK could be landed with given the worst (for the UK) interpretation of a wide range of plausible criteria about what might or might not be included in any settlement. You have to make some quite one-sided assumptions to get to a figure this high, and typically the reports where these kinds of figures come from do show this, though of course headline writers don't tend to incorporate such nuance.
Secondly, even if it were some sort of official figure, it would be politically untenable for the UK to accept it. The UK's net contribution to the EU as a member enjoying full membership benefits is about an order of magnitude smaller. The EU plans budgets on a 7-year cycle (the current one is 2013-2020) but the actual budgets are made annually. Those budgets normally do commit to future spending with quite a long tail, but the curve is very front-loaded and most money committed in any given year's budget is usually to be spent within 2-3 years.
So a figure in the region of £100B would be like asking the UK to pay for around another decade of full membership after it's left, a period far beyond most current spending commitments the EU is making. Moreover, the current EU position is that this needs to be negotiated independently, before any deal on any benefits the UK might retain in some form as a result of any future agreement or payments, so there would be little if any guarantee about the UK getting anything in return for that extra financial support to the EU.
Personally I'm still hoping for the professionals to take over from the politicians and come to a reasonable agreement. I don't think they have much chance of doing that in less than 2 years, but with an extra 2-3 years of some sort of transitional arrangement, it doesn't seem impossible. They could deal with the budgeting issues and current financial commitments at that notice, allowing a more graceful withdrawal by the UK without either anyone feeling they'd had funding cut off abruptly on the EU side or the UK putting up either a huge lump sum or any sort of ongoing financial support to the EU without getting something worthwhile in return.
Firstly, it's not an official figure but rather an estimate by outside observers of the maximum bill the UK could be landed with given the worst (for the UK) interpretation of a wide range of plausible criteria about what might or might not be included in any settlement. You have to make some quite one-sided assumptions to get to a figure this high, and typically the reports where these kinds of figures come from do show this, though of course headline writers don't tend to incorporate such nuance.
Secondly, even if it were some sort of official figure, it would be politically untenable for the UK to accept it. The UK's net contribution to the EU as a member enjoying full membership benefits is about an order of magnitude smaller. The EU plans budgets on a 7-year cycle (the current one is 2013-2020) but the actual budgets are made annually. Those budgets normally do commit to future spending with quite a long tail, but the curve is very front-loaded and most money committed in any given year's budget is usually to be spent within 2-3 years.
So a figure in the region of £100B would be like asking the UK to pay for around another decade of full membership after it's left, a period far beyond most current spending commitments the EU is making. Moreover, the current EU position is that this needs to be negotiated independently, before any deal on any benefits the UK might retain in some form as a result of any future agreement or payments, so there would be little if any guarantee about the UK getting anything in return for that extra financial support to the EU.
Personally I'm still hoping for the professionals to take over from the politicians and come to a reasonable agreement. I don't think they have much chance of doing that in less than 2 years, but with an extra 2-3 years of some sort of transitional arrangement, it doesn't seem impossible. They could deal with the budgeting issues and current financial commitments at that notice, allowing a more graceful withdrawal by the UK without either anyone feeling they'd had funding cut off abruptly on the EU side or the UK putting up either a huge lump sum or any sort of ongoing financial support to the EU without getting something worthwhile in return.