Other airports across the country have also been affected and the problem is having a particular impact on non-EU airline customers.
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With just three days to go until polling stations open, representatives from all parties were out in force across the capital today.
The garden above the Canary Wharf Crossrail station is now open to the public.
First time buyers in London now need an average annual income of £77,000 - nearly double the amount required in the rest of the country.