It is very rare for a credit card company to pursue a consumer for fraud under circumstances like these because you can show a pattern of using the card in this manner for quite some time before your financial difficulties. While it will certainly be more difficult to get the notices and information to you in the UK, Amex can sue you in the county of your last address in the US and then obtain a default judgment against you. They can then either wait until you return to the US to try to collect on the judgment or they can take the judgment into a UK court and have it certified by that court and try to collect from you there (you would have to ask a UK lawyer what the collection efforts are like there on a US judgment being brought into the UK -- Just Answer DOES have a very large UK section so you can seek that out after this). If at all possible, you might consider bankruptcy as an option before you leave the US and that will either wipe out the debt (Ch 7) or let you structure a payment plan over 5 years for unsecured debt (CH 13 - they are paid a few cents on the dollar and then you are written off). Whether you can declare a Ch 13 or Ch 7 bankruptcy depends upon your income.
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