The party says it has drawn up a roadmap to bring democracy to Zimbabwe, but central was Mugabe relinquishing control.
"Zimbabwean President Robert Mugabe cannot be part of the process," the party said in a statement.
"The position he currently holds is illegitimate and as a result, his interests and the interests of those close to him have compromised the current arrangement."
The DA said its roadmap proposed that an agreement be reached whereby Mugabe willingly stepped down from power. "This exit package in turn, will only work if there is a united front behind it.
"The time for accommodating the undemocratic behaviour of Robert Mugabe and Zanu-PF is over and the focus needs to shift from appeasement, to outcomes."
The roadmap consisted of an agreement to hold fresh elections in Zimbabwe, the formation of an interim government, the formation of a new constitution and democratic elections.
"Now, more than ever, we need a clear plan of action on Zimbabwe.
We need the regional and international community to unite and we need the South African government to play a defining role in this regard."