USA Can US expats living in UK contribute to a Health Savings Account (HSA)?

[neekolas86]

Are US expats living in the UK eligible to participate in a high deductible health plan (HDHP) thus allowing them to contribute to a health savings account (HSA)?

IRS Publication 969 does not address expats living in a country providing socialized health care (see page 3, Qualifying for an HSA).

Thanks!