Robert Mugabe is reportedly fighting for his life in a hospital in Singapore, although a party official said he is simply on his "Easter holidays".
An unnamed senior Zanu-PF official told the Zimbabwe Mail the president is undergoing intensive treatment in Singapore and his family have boarded a chartered plane to join him.
Mugabe reportedly collapsed in his home last week.
The 88-year-old is believed to be suffering from prostate cancer, according to a 2008 US diplomatic cable leaked by Wikileaks.
However a second party official denied Mugabe had a health emergency, and was to return to the country on Wednesday after holidaying with his family.