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My partner is Russian with a Russian passport, but has a Netherlands residence permit and has lived in the Netherlands for over 7 years.
What is required for her to enter the UK?
Other info which is likely important: her Dutch residence permit needs to be renewed on 27th Feb 2018, and travel to London is 14th February 2018.
She's currently checking into the process for acquiring a Dutch passport but in case it's not completed in time ...