Montreal (dpa) - Climate activist Greta Thunberg has demonstrated in the Canadian city of Montreal at the end of an international strike week together with about half a million people for more climate protection. At the same time, at a meeting she accused Canadian Prime Minister Justin Trudeau of failing to adequately tackle climate change. In the afternoon, Trudeau and Thunberg participated in a climate protest in Montreal. Trudeau announced that it would plant two billion new trees in Canada in the event of an October victory.