Following Brexit, the formalities to go to the United Kingdom will change as of October, 1st 2021. Indeed, if you a member of the E.U., previously when a simple National Identity Card was OK, you will now need to bring your valid passport (at least for the duration of your stay in the UK) to cross the border.
If you want to stay in the UK for more than 6 months (relocation, porfessional potivations,…) then, you will surely need a Visa in addition.
You are (live) in the UK before 2021, then an exception is made and you can still use your National ID card but please note up to 2025 only.
A question? Any doubt on these new procedures? You need a Visa?
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