Call out the blockades for what they are - illegal acts of extortion - and pressure the Premiers to have them end the blockades.
with a focused and repeated emphasis on required dialogue, PM Trudeau has also repeatedly spoken of the need for protestors to respect the rule of law; i.e., they're acting unlawfully in terms of injunctions issued by the respective provincial judiciary. PM Trudeau has also, several times now, acknowledged the most significant impacts the blockades are having. The word, your wanted word, "extortion" is not, quite obviously, conducive towards successful dialogue; a word, your wanted word, fitting the Conservative/CPC mould reflected by the recent words of CPC leader/candidates, weakAndy, mmmKay, O'Tool, etc..
perhaps you could further elaborate on what you mean/imply with your words "pressure the Premiers". Make sure to include, by extension, exactly what you believe/interpret the provincial Premiers can... should do; specifically so, particularly as to my inference that you're expecting political direction of law enforcement, ala police-state infringement upon democracy, upon democratic society.