Harare - Zimbabwe President Robert Mugabe on Saturday warned some ministers will be axed in a shake-up of his cabinet amid deepening infighting in his Zanu-PF party over who succeeds him."I do my own review to assess who have not pulled up or lived up to expectations in government. In the process some will fall," he told youth league members at a meeting at the party's headquarters."So, that exercise I will be doing early next week."Mugabe's announcement came amid escalating tension between rival factions jostling to succeed the 93-year-old - including his lieutenants and his wife.One of his two vice presidents, Phelekezela Mphoko, claimed his counterpart, Emmerson Mnangagwa, had lied about being poisoned at a party rally in August.Mugabe's wife Grace then angrily accused Mnangagwa - the frontrunner to replace the president - of dishonesty, alleging that some unnamed people were plotting a coup if their candidate did not succeed him.The president last reshuffled his cabinet in 2015 after firing allies of former vice president Joice Mujuru, who was dismissed over allegations of plotting to unseat him. Mujuru denied the charges.Mugabe's 52-year-old wife is also seen as eyeing her husband's seat in the event of his death or retirement.Despite his age and signs of frailty, Mugabe has avoided naming a successor, even after his wife pressed him to do so at a recent party meeting.His party has endorsed him as its presidential candidate to face a coalition of opposition parties in general elections next year. Mugabe also called for unity and an end to public squabbles over his succession."If there are problems, let's discuss them," he said as his wife and both deputies sat flanking him."Insulting each other is a shame."