Transport minister Norman Baker has announced that a main London commuter route will be chosen to trial part-time season tickets.
Speaking at the LibDem conference in Glasgow, he said it was unfair that those who work five days a week should benefit from cheaper travel than part-time workers.
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The capital's theatres also generate more searches than those in any other city, according to research by Google.
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.