Juncker urged European firms on Tuesday to boost their investments in Africa in a "partnership among equals," reminding the joint European Union and Africa Union forum that Africa's population was forecast to double to 2.5 billion by 2050.

"Africa's future is also our [European] future," said Juncker in opening remarks to representatives of 800 businesses and political leaders gathered in Vienna.

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Asked if Europe was too late in discovering business investment opportunities in Africa, Juncker replied: "Yes, but we do it better."

Hosting the forum with the AU's current chairman, Rwanda's President Paul Kagame, Chancellor Kurz of Austria — which holds the rotating EU presidency and is an advocate of strict European rules on migration — said: "We must not leave the African continent to China," describing Tuesday's forum as a "good start" for more investment by Europe beyond the Mediterranean.

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In September, Beijing hosted African leaders at a summit, offering billions. Last year, China opened its first overseas military base in Djibouti and ranks as Africa's largest trading partner, followed by Japan and the EU (taken as a single entity), according to EU statistics.

Among EU nations, the highest surpluses in trade with Africa last year were accrued by Germany (€8.3 billion) and France (€ 5.6 billion).

"It's better to start than not start at all," said Namibian Communications Minister Stanley Simataa in Vienna Tuesday, saying past colonial "dark chapters" were part of the "shared history" of Africa and Europe.

Austria chided for anti-migrant stance

Austria's recent avoidance of the UN migration pact adopted by 164 nations in Morocco was criticized as a "surprise" by AU commission chairman Moussa Faki Mahamat.

European heavyweights like Germany, France and Italy only sent ministerial level officials to the Vienna investment forum, according to a forum list of attendees: Those present included presidents and premiers from Egypt, Ethiopia, Guinea, Kenya and Mauritius.

Climate warning for African mega-cities

Siemens CEO Joe Kaeser said that the German giant planned to invest an additional 500 million euros ($567 million) to provide infrastructure, including "affordable" electricity, on the African continent.

Africa's burgeoning mega-cities include Congo's Kinshasa, Nigeria's Lagos, Egypt's Cairo, Tanzania's Dar es Salaam and Angola's Luanda, faced "extreme risks" from climate warming, warned the Britain-based research team Verisk Maplecroft in a study last month.

Kinshasa, now at 13 million and set to double in population by 2035, risked extreme flooding. Luanda would struggle with high heat levels, as well as water shortages, it added.

ipj/msh (dpa, Reuters, KNA)