The boats - repainted and pulled around on trailers - have become a symbol of the group's demonstrations and were used to stop traffic in five British cities this week as part of a “summer uprising.” In April, a pink boat was used to block major roads and cause traffic chaos around Oxford Circus junction in central London.
Police warned on Thursday that the April protests were unacceptable and they would not tolerate that level of disruption again.
“We need to balance [their right to protest] with the rights of those wishing to go about their daily lives and action will be taken against those who choose to ignore this condition and/or break the law,” said Commander Jane Connors.
Police said the boats would be banned for Friday's demos, which began with a protest at the construction site of London’s 4.2 billion-pound super-sewer project.
Extinction Rebellion says it wants to cause even greater disruption in October than it did in April, when protests included stopping trains and defacing offices of oil major Shell.
It aims to use non-violent civil disobedience to force governments to cut carbon emissions more quickly.