Harare - The battle to succeed Zimbabwean President Robert Mugabe crossed over into 2017 with internal squabbles in the fractious ruling Zanu-PF party being taken to a coffee mug.Mugabe's deputy, Emmerson Mnangagwa, who is tipped to take over from the nonagenarian, torched a storm when he appeared on social media holding a coffee mug inscribed "I am the boss".See a tweet with Mnangagwa's coffee mug below. Mnangagwa, who is the acting president in the absence of Mugabe who is on holiday in the Far East, is reportedly leading a Zanu-PF faction calling itself "Team Lacoste" that is angling to take over when Mugabe eventually leaves office. Another camp, made up of young Turks calling itself Generation 40 or G40, is backing First Lady Grace Mugabe to succeed her ageing husband.Following the release of the controversial picture featuring Mnangagwa and a pro-Zanu PF musician and businessman Energy Mutodi, one of the key members of G40 and Higher Education Minister Jonathan Moyo took to his Twitter account lambasting Mnangagwa. "...Everybody knows that the Boss is Gushungo (Mugabe). One Boss at a time, please! Kumhanya hakusi kusvika veduwe (There is no need to rush).'Signs of poor reasoning'Not to be outdone, Mutodi, who is a staunch supporter of Mnangagwa, also took to his Facebook discrediting Mugabe and heaping praise on Mnangagwa.Mutodi warned Mugabe that he risks isolating himself if he continues to protect the G40 faction citing a case in which Moyo stands accused of siphoning close to half a million dollars of public funds from the Zimbabwe Manpower Development Fund (Zimdef). "The veteran president (Mugabe) has also recently shown signs of poor reasoning when he fell prey to a G40 ploy to isolate him from his support base, mainly war veterans who delivered the country's independence," said Mutodi.MOYO FUMES OVER MNANGAGWA’S I’M THE BOSS CUP https://t.co/0PfCf3nx6M pic.twitter.com/jpBFjEfmzO— ZiMetro (@Zimetro) January 3, 2017War veterans recently issued a damning communique indicating that they would not campaign for Mugabe ahead of elections due next year. They argued Mugabe’s candidacy would be a hard-sell because of his advanced age and a faltering economy.Mutodi called on Mugabe to step down, accusing him of failing to properly run the affairs of the country. 'There will be no silence'However, Moyo declared war on Mngangagwa and anyone discrediting Mugabe. He wrote on his Twitter account that "there will be no silence when President Mugabe is systematically and daily attacked by surrogates who take a mug-pose and then attack the president". Zanu-PF national spokesperson Simon Khaya Moyo declined to comment on a war of words between the two factions."I only comment on matters of policy and issues to do with the party; I have not yet seen the war on social media that you are referring to," said Moyo. Mugabe has failed to groom a successor since 1980 when he took over the leadership of the southern African country from British colonial rule in 1980. His advanced age has also fuelled the succession debate within his Zanu-PF party.