Isle of Man bus drivers are planning to strike during the TT fortnight.
Strike days will be announced seven days in advance and timed to cause maximum disruption, according to Unite the Union.
Bobby Morton, Unite’s national officer for passenger transport, said: “We’ve got disputes scheduled for the last week in May and the first week in June.
“The drivers will be trying to cause as much disruption as they can. Otherwise there is not point.”
He said the TT had been chosen because it was the most profitable time of year for the government-owned service Bus Vannin.
It will be the drivers’ fifth walkout since December in a dispute with Bus Vannin over plans to cut their wages by £3000 a year.
Eric Holmes, Unite's regional officer for the Isle of Man, said 73 of 77 drivers voted in favour of action.
The Manx Department of Community, Culture and Leisure is aiming to save about £1m a year to help plug a £75million hole in the island’s income after the UK ended a VAT sharing agreement.
A DCCL spokesman said TT fortnight was the busiest time of year for buses, with many visitors using them after drinking. He said: “We’re going to do everything we can to make sure the impact is minimised.”