Zimbabwe’s former vice president Emmerson Mnangagwa, who was sacked by President Robert Mugabe this week, has been expelled from the ruling Zanu-PF, a party spokesman said on Wednesday.

Zimbabwean President Robert Mugabe (C) holds hands with Vice President Emmerson Mnangagwa (L) and First Lady Grace Mugabe (R) during celebrations marking his birthday at the Great Zimbabwe monument in Masvingo on February 27, 2016. / AFP / JEKESAI NJIKIZANA (Photo credit should read JEKESAI NJIKIZANA/AFP/Getty Images)

Mnangagwa, a liberation war veteran and a long-time ally of Mugabe, was until this week seen as a favorite to succeed the 93-year-old leader.

But Mnangagwa’s relationship with Mugabe’s wife, Grace, has become increasingly strained as their two factions within Zanu-PF fight for dominance. Mnangagwa’s removal on Monday came two days after Grace publicly called him a “coup plotter”.