The first thing that you need to know in this respect is that all rules and regulations related to entrance in United Kingdom is taken care by UK Border Agency. But things are different in UK than US, englishmen do not have what you call ‘visa waiver programme’, so it doesn’t matter who enters USA or what is their purpose of visit they ought to have a visa to stay in the country. So, all those looking for Spouse visa London or visa for joint venture for London would need ro though same procedure. But with respect to US, it has been included among ‘designated countries’ in Britain which means American citizens arriving here for business or tourist purposes can easily apply for visa after landing in UK.
The englishmen follow a very precise definition of business and tourism. Every unpaid member arriving here weather for tourism, marriage, internship, student, partner, parent, charity, religious worker, or child will be counted in the dependent category will need to clear the entrance test in UK before landing here. It doesn’t matter what is the purpose of your visit or duration of your stay, you will need to clear the entrance.
With respect to tourist visa, every US citizen entering UK would need to adhere to the regular routes of immigration. Tourist visas stay valid for any time slot varying from one day to six months. However, there are a few prerequisites you are expected to meet such as you would need to ensure that you are not visiting the nation for more than six months and you have enough financial account to support yourself without working or collecting public funds. In case, you are visiting for business purposes need to ensure that they are entering the nation only for temporary periods and not planning to transfer your business base to this nation. Also, you need to show that you are getting your salary from abroad and you are not into selling and buying of goods directly in public areas. You are not coming to replace anyone in UK including temporary leave periods. Lastly, it needs to be clarified that you are not landing in UK for internships or placements. If you are coming for civil partnership or marriage, you will need to know the UK partner Visas rules for American Citizens in detail.
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