TENNIS coach Judy Murray suffered a "tourist trauma" after being thrown off one of London's new cashless buses when she tried to pay with coins.

Ms Murray demanded an explanation from the city's mayor, Boris Johnson, after being ejected from the capital number 22 service on Monday.

In an angry riposte, Andy Murray's mother tweeted: "Got chucked off the 22 bus on New Kings Rd today. You can't pay cash on London buses apparently. What is that all about Boris? #touristtrauma."

London introduced the cashless buses in July last year in response to the dwindling number of passengers paying by cash.

At the time, Transport for London said 99 per cent of travellers had already switched to Oyster cards, prepaid tickets, contactless payment cards or concessionary tickets.