Johannesburg - A Zimbabwean pastor who is using social media to take on President Robert Mugabe's government says he hopes his countrymen can peacefully achieve reform in the southern African country.Evan Mawarire, 39, told The Associated Press that Mugabe's Zanu-PF party is destroying itself.Mawarire is currently in neighbouring South Africa after launching a social media campaign, #ThisFlag, which has seen Zimbabweans wave and wear their flag as a sign of protest against the Mugabe government. Over the weekend, protesters waved flags and sang the national anthem at a cricket match against New Zealand in Bulawayo.Mawarire said he is not seeking to become a political leader who unseats Mugabe. "In terms of me being the person, I don't know," he said. "I want to make sure that I exhaust my role as a citizen leader as best as I can, so that we leave our generation in a position to be able to move forward."Mawarire left Zimbabwe after being arrested and briefly spending time in a cell last month. He said he had not been in touch with opposition parties in the country, nor with a group of war veterans who have strongly criticised Mugabe after being some of his closest loyalists for decades.Mawarire's campaign comes as Zimbabwe's economy is collapsing amid a cash shortage that has prevented the government from paying nurses, doctors, teachers and police. Last month, people across the country staged the largest anti-government strike in nearly a decade.Mugabe, who has been in power since 1980 and is the world's oldest head of state at 92, has responded by saying that people who aren't happy should leave the country.