The African Union said Saturday Africa had "lost one of its great sons" after divisive president Bingu wa Mutharika died in office.
"He was rightfully credited with boosting Malawi's economy, especially in the agricultural sector," AU Commission Chief Jean Ping said in condolences sent to new President Joyce Banda.
"We in the African Union Commission will fondly remember the late President for his Chairmanship of the African Union from January 2010 to January 2011, during which he laid down a roadmap for Africa to achieve food security and sustainability."
Mutharika died after a heart attack on Thursday amid calls for his resignation following deadly anti-government protests last year accusing him of wrecking the economy and trampling on democracy.
He was to host the next African Union summit in the capital Lilongwe in July. Banda was on Saturday sworn in as Malawi's first woman president and told her supporters there was "no room for revenge" after Mutharika's sudden death.
The European Union also remembered the late leader "as a champion of food security in Africa and for his success in achieving national food security in Malawi.
"Malawi has in the past 20 years become an example of democracy with its peaceful transitions of power and respect for the constitution and the outcome of elections," said a joint statement by Herman van Rompuy, president of the European Council, and Jose Manuel Barroso, president of the executive European Commission.
"We express our hope that this tradition will be respected and that there will be a calm and peaceful transition of power in full respect of the provisions of the Constitution," they added. -Sapa-AFP