A vessel receiving a route suggestion can choose to respond to the sender with the following message.
Jens Kristian Jensen Danish Maritime Authority JKJ@dma.dk [1]
Links[1] mailto:JKJ@dma.dk [2] http://enav.frv.dk/ais_route_suggestion.pdf [3] https://www.e-navigation.nl/sites/default/files/asm_files/message_exchange_for_flow_management_in_maritime_traffic_management_systems.pdf