US Dollar Gifts and UK Tax

Like Mimsy, I received a Christmas cash gift from my parents (in the USA) that I would like to being over to the UK, where I pay income tax at the 40% rate. The amount of the gift was within the tax-free parameters set out by the IRS, but I have no idea how the Inland Revenue will view it. Will the Inland Revenue regard it as income? If not, is it liable to UK tax in any other way? Do I have to declare it on my UK return?
Many thanks in advance for any advice.

I was told by another US ex-pat that if it came from an interest bearing account then the Inland Revenue would tax it... I don't know if that's true, but I would definitely try to find out.