The Offshore is the best option, and also saves you taxes.
Try barclays offshore or lloyds tsb offshore. They allow you to trasnfer money from the USA to the island of man or jersey, then you earn interest without payiing the UK taxes, it is legal, the concept here is:
as long as you are not permanently resident or citizen your income abroad is tax free, if you don't bring the money into the UK.....so you can keep your money in jersey and have a small amount at your disposal in the Uk.
Barclays
www.barclays.com has offshore facilities for foreign nationals, accounts can be in pounds or dollars (your bet) and you can use those accounts to manage your money....