Boris Johnson has refused to comment on reports that West Ham have reached an agreement with City Hall, on the share-out of any profits if the club were to be sold after moving into the stadium.
West Ham were named preferred bidders for the Olympic Stadium in December last year - but the parties have since been hammering out the details of any potential deal.
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Negotiators from London Underground and three unions are meeting at the Euston offices of the concilliation service ACAS.
Clear periods and light winds tonight. Staying warm and muggy. Lows of 17°C.
It took police six days to launch a murder investigation after notorious British criminal John 'Goldfinger' Palmer was shot dead.