"We must remind those behind the current treacherous shenanigans that when it comes to matters of protecting our revolution, the military will not hesitate to step in", he said, adding that the instability was causing anxiety in the country.
"The current purging which is clearly targetting members of the party with a liberation background must stop forthwith", Chiwenga told a media conference in the capital, Harare.
Chiwenga, speaking alongside the commanders of the army and air force, was commenting on the upheaval in the ruling Zimbabwe African National Union-Patriotic Front following Mugabe's dismissal of Emmerson Mnangagwa, 75, as vice-president a week ago and his subsequent expulsion from the ruling party.
Flanked by some 90 senior military commanders, General Chiwenga addressed journalists at army headquarters.
Mugabe, in the last few years, has uncharacteristically lashed out at the military for meddling in the political mudslinging in Zanu PF and especially the succession issue while his wife Grace has consistently accused army generals of ulterior motives. Mugabe, 93, was "now virtually unable to walk without assistance, always needing the support of his wife, Grace, and the phalanx of bodyguards he travels with", the report said. Meanwhile, critics maintained that the former vice president had become a "stumbling block to First Lady's ambitions to succeed her husband".
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Former treasurer Peter Costello blocked Shell's attempted $10 billion takeover of Woodside in 2001 on national interest grounds. Logos of Woodside Petroleum are seen at Gastech, the world's biggest expo for the gas industry, in Chiba, Japan, April 4, 2017.
While Mugabe has insisted the wartime maxim of "politics lead the gun" would be the compass that should provide the military with direction Chiwenga argued: "It is pertinent to restate that the Zimbabwe Defence Forces remain the major stockholder in respect to the gains of the liberation struggle and when these are threatened we are obliged to take corrective measures".
Mnangagwa who had been touted as an obvious successor to Mugabe, fled into exile this week.
Chiwenga said ZANU-PF had since 2015 been rocked by infighting, which had afflicted the economy, causing serious cash shortages and soaring prices of basic commodities - rare criticism of those in government by the military.
In a statement, Gen. Chiwenga said the military derives its mandate to intervene from the Constitution of Zimbabwe.
The war veterans invited all cadres expelled from the ruling Zanu PF to come and chart the way forward.