Across the world, embassies are considered to be territory of the country who's embassy it is.
Thus diplomatic staff working at their embassy are not working in the host country but in their home country.
Diplomats of an embassy would enter a country using a diplomatic passport issued by their country. A diplomatic passport infers on the bearer immunity from many of the laws of the host country (although diplomats are meant to respect the local laws). For instance the embassy would not pay rates and diplomatic cars frequently flout parking restrictions (with impunity).
Thus diplomats would not need a visa to work in the host country but would need a diplomatic passport.
No, you generally need a visa to work in the UK as a foreign national.
No, you generally need a visa to work in the UK if you are not a citizen or a resident with the right to work.
If you get the UK work visa then the work permit is not given to US so you need a work permit for US.
A work visa
Yes, you generally need a visa to work in the UK if you are not a British citizen or a citizen of a country within the European Economic Area (EEA) or Switzerland.
Some frequently asked questions about UK visa applications include: What type of visa do I need? What documents do I need to provide? How long does the application process take? Can I work or study in the UK with this visa? What are the visa fees?
You can establish your own business in the UK if you have the UK work visa.
No need for a visa, as the UK is a participant in the Visa Waiver Program.
She would need a UK work visa.
if you have a current valid British passport you are recognised as a British citizen, therefore you do not need a visa to work in the UK. You can also get the full information from Visa Simple, that provides bespoke support to their clients and customers.
No, a UK visa is only valid for the UK. You need a "Schengen visa" for Switzerland.
As an American citizen, to work in the UK you generally need a work visa or permit. The type of visa you need depends on the job you have been offered and your qualifications. There are restrictions on the types of jobs you can do and the length of time you can work in the UK without a visa. It is important to research and understand the specific requirements and restrictions before seeking employment in the UK.