The Alliance of British Drivers is calling for the tolls at the Dartford crossing to be scrapped completely.
The Government plans to remove the existing barriers by autumn next year but motorists will still have to pay to use the crossing by phone, text or online.
The Alliance says the free-flow charging will cause inconvenience for drivers having to remember to pay and that they risk getting fined if they forget, plus the hassle of running such a system.
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Any lingering showers clearing into tonight with a mostly dry but chilly night ahead. A cool but sunny start to Sunday.
Further heavy showers gradually clearing away this evening. Dry but chilly tonight, then dry with plenty of sunshine tomorrow.
Heavy showers turning potentially thundery this afternoon. Becoming dry but chilly tonight, then dry and sunny tomorrow.