Complex sentence: With a total retail floor area of, it will be the largest urban shopping centre in Europe and will become the the largest shopping centre in the UK, taking the title from the MetroCentre in Gateshead.
Split into simpler sentences: With a total retail floor area of, it is claimed to be the largest urban shopping centre in Europe. Upon completion, it will become the the largest shopping centre in the UK, taking the title from the MetroCentre in Gateshead.