Cord leader Raila Odinga has lauded Tanzania's President Jakaya Kikwete for steering a credible and democratic leadership transition.
Raila emphasised the need to adhere to constitutional term limits for African leaders, during their meeting on Monday.
The two leaders met in Dar es Salaam before Raila left for Zanzibar where he will give a keynote address during the East African Global Peace Leadership Conference.
Raila and Kikwete held discussions on regional peace and stability, following increasing cases of terror attacks and extremism in East Africa.
They further discussed the promotion of good governance, democratic practices and regional socio-economic integration with a view to easing bilateral trade.
Tanzania's Prime Minister Frederick Sumaye was among those who saw Raila off at Mwalimu Julius Nyerere International Airport.
The country's ruling party named Works Minister John Magufuli as its candidate for the October 25 presidential race.
The Chama Cha Mapinduzi party has ruled Tanzania for five decades and its candidate is widely expected to succeed Kikwete, who has served a maximum two terms.
Tanzania has been one of Africa's most politically stable nations and has not been torn by the debate raging in parts of the continent, where some presidents have sought third terms despite constitutional restrictions.
Others expected to attend the four-day Zanzibar conference, that begins on Tuesday, are Zambia President Rupiah Banda and former presidents Amani Abeid Karume (Zanzibar), Olusegun Obasanjo (Nigeria) and Sir James Mancham (Seychelles).