People must confront the "myths and wilful distortions" perpetuated by the anti-free trade lobby, Liam Fox is set to say.
The International Trade Secretary will call for people to champion the benefits of free trade - claiming there is both a "democratic duty" and "responsibility" to build the case - in a speech at the Speaker's House on Monday.
Dr Fox will say that for too long the argument has been focused on misleading claims about food standards, and that he wants to move the spotlight onto opportunities that can come from the global market.
"It would be a major political mistake to assume that the case for free trade is so self-evident that it does not require champions today," he expected to say.
"We have seen the way in which trade agreements such as the EU's proposed agreement with United States (TTIP) produced violent reactions, however carefully orchestrated, in traditionally free-trade countries such as Germany.
"We need to distinguish between the violent anti-capitalists and the legitimate concerns of those worried about the effects that free trade and the development of new technologies may have on their own jobs and communities.
"We need people - to confront the myths and wilful distortions perpetuated by the anti-trade lobby.
"It is not only our democratic duty but our responsibility for the generations to come to build the case for free trade by making coherent arguments that are attractive across the political spectrum."
Dr Fox will also warn that future generations will be denied the benefits of free trade if Britain is not willing to "take head-on the deceptions of the anti-trade lobby".
"They peddle the irresponsible myths that agreements such as the new EU trade agreement with Canada, CETA, will result in reduced protection for workers, a degradation of food and environmental standards and the forced privatisation of organisations like our NHS. Such false claims are as dangerous as they are pernicious."