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Very broadly, you'll always be able to reg and sell generic domains, i.e. domains that contain generic terms, e.g. dvdplayers.co.uk, but what you can't do is attempt to make money by purporting to be someone you're not and using their registered intellectual property, e.g. sonydvdplayers.co.uk.
I personally think visit*countryname* would probably not have a UK registered trademark so you're probably ok, although the UK tourist board does use visitbritain and that probably wouldn't be ok.
Have a look at the Nominet DRS cases to get a feel for the subject and there are plenty of old threads on this forum.