I didn't understand what Darling said either!
AIUI, under the agreement between the Icelandic and UK governments, Iceland is responsible for the first so many Euros (is it 25,000 - I can't remember) and the UK for the difference between this and 50,000.
What was not at all clear to me is whether - if Iceland defaults on its obligation, as looks likely - the UK goverment will pick up the tag - or whether they will only pay what they *would* have paid under the original agreement. If the latter, anyone who has less than the Iceland share - such as my son - will get nothing at all.
Can anyone clarify?