Speaking at the ruling party Zanu-PF's annual conference today, Mugabe said Joice Mujuru has attended secret meetings at the embassy in Harare.
Mujuru was removed as the party's vice president during the three-day conference, but she remains the country's vice president.
The party conference re-elected the 90-year-old Mugabe to another five-year term as leader of the party.
Mugabe was also authorised to personally choose his vice president and other top party posts.