The UN will never pay local taxes or even rent. No permanent UN staff has their salary taxed either. That's why their main HQ moved to New York and there's no real UN presence in the UK, Gordon Brown tried to make them pay rent.
Actually i think you will find that they do Its under the guise of staff assessment not tax, but in line with UK tax deductions no difference just a different name
Er, no. Staff assessment may be on a par with UK taxes but it is not in fact a tax, it is a UN a contingency fund, and it doesn't go to the UK exchequer.
Not one to nit pick over finer details I feel I must point out that as you stated ... 'The UN will never pay local taxes or even rent....' I think if you delve a little deeper you will find that the staff assessment deductions will be used to pay state taxes to any country that so wishes sooooooooooooooo If this is requested in Gambia these taxes will be paid.
Incidently depending on the nation they are on Par not just the UK