Lord Deighton says to London Assembly member John Biggs that many tickets were sold below market value - 340,000 tickets were given to school children and troops.
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Union officials are expected to meet next week to plan further stoppages if talks fail to resolve the dispute.
Natalie Sharp and Christine Bicknell appeared in court over an alleged incident at a Lidl superstore in Wallington, south London.
Dry with clear spells periods across the south tonight, further north, cloudier conditions bring the chance chance of light showers.