SAO PAULO - Independent truckers in Brazil plan to start an indefinite strike on Monday, according to a leader of the movement that slowed deliveries of food, fuel, and industrial supplies earlier this year. Protest leader and truck driver Ivar Luiz Schmidt said the government had not addressed the demands of drivers, such as a national minimum freight rate and diesel fuel subsidies. A two-week strike in late February this year blocked roads at more than 100 sites in six states, but calls for a new strike in April had little effect. The latest plans come at a time of deepening discontent in Latin America’s largest economy. Approval of President Dilma Rousseff’s government is at a record low and oil workers at state-run Petrobras are in the middle of their most disruptive strike in 20 years. The Facebook group National Transport Command, which has more than 27,000 followers, posted photos of trucks with “Nov. 9 strike for Brazil” scrawled across their windows.