German Vice-Chancellor Robert Habeck hopes to use planned farmer protests during his visit to the western city of Mainz on Thursday as a chance for dialogue with the demonstrators. A convoy of tractor-driving farmers have announced a protest in Mainz, part of a wave of demonstrations against government plans to eliminate a diesel fuel subsidy for the agricultural sector. “The farmers naturally have concerns and needs which, in my view, go beyond the agricultural diesel discussion,” Habeck said on Thursday. He did not know whether they could all be resolved in the evening, “but if there is a ch…