UK deductibility of Roth contributions

Hello all,

This forum has already provided invaluable information, but I have an unresolved question.  I'm a US citizen moving to the UK this fall.  My employer offers both traditional and Roth 401(k) plans, that will be started while I'm still employed stateside.  I was informed that regardless of US tax treatment, contributions to both plans would be deductible from my UK taxes.

Is that so?  I've looked at the treaty, and I'm somewhat suspicious of that advice, because then it'd be a no-brainer to go Roth - I get the benefits of UK deduction and tax free growth and withdrawal, all for the low, low price of using up a little more of unused Foreign Tax Credit.

Thoughts?  Links?  Thanks!

This might help: http://www.hmrc.gov.uk/cnr/res-dom-faqs.htm

Thanks - I saw that, but as far as I can tell it deals with withdrawals.  I was hoping to understand better the taxation of contributions.