Petition over Greater London boundary charge reaches 25,000 as Dartford Labour joins in opposition to Mayor's proposals | Updated: 10:56, 17 February 2021 A petition calling on the London Mayor to drop "disastrous" plans to charge Dartford motorists crossing into Greater London has surpassed 25,000 signatures â and has drawn opposition from the Labour party. In two years' time it could cost £3.50 for north Kent residents to drive into the neighbouring borough of Bexley. Dartford residents hit out at proposed Greater London boundary charge The Greater London Boundary Charge is among the ideas put forward by the Mayor Sadiq Khan (Lab) to raise an estimated £500 million a year for cash-strapped Transport for London (TfL).