Ethiopian Prime Minister Abiy Ahmed is facing opposition from one of his closest allies in his proposal to merge the ruling coalition into a new party.

Defense Minister Lemma Megersa said he disagrees with the rushed merger of political parties, according to an interview with the Voice of America. Lemma is the deputy chairman of Abiy’s Oromo Democratic Party.

Lemma Megersa Photographer: Zacharias Abubeker/AFP via Getty Images

Lemma said he also opposes Abiy’s new philosophy to unite the country, called “Medemer,” directly translated as “to add.”

Lemma’s comments come ahead of general elections expected in 2020, raising more challenges to the success of a new unity party. The merger has the support of all coalition members, even though it faced opposition from Tigray People’s Liberation Front, which was a former leading member.

The ruling coalition has been in power for 30 years in Ethiopia, Africa’s second most populous country. The Nobel Peace Prize-winning prime minister has vowed the general election would be democratic.