The Civic United Front (CUF) chairperson Ibrahimu Lipumba has resigned.

In a move that will likely weaken Ukawa, an alliance of major opposition parties Lipumba accused the opposition of welcoming the ruling Chama Cha Mapinduzi defectors who did not support Judge Joseph Warioba’s Proposed Constitution –reason the opposition parties came together-.

Lipumba’s resignation comes a week after Ukawa nominated former Prime Minister Edward Lowassa its presidential candidate via main opposition party, the Chama cha Demokrasia na Maendeleo (Chadema).

"It goes against my conscience to welcome such leaders into our coalition," Lipumba told a news conference.

Chadema previously named Lowassa in its 'List of Shame' of government leaders tainted with graft accusations.

Lowassa quit as premier in 2008 over corruption allegations that he denies.

Lipumba who has stood for the presidency three times said he would remain an ordinary CUF member and engage in his profession as an economist.