It may have involved some difficult negotiations but António Pires de Lima, head of the Portuguese drinks group Unicer, last month finally won permission to build a brewery in Angola. Not only did it cement a €100m deal, more strikingly it encapsulated an intriguing historical twist: his country's re-engagement with its rapidly growing former African colony.

Unicer's investment confirms Portugal's position as – outside the oil sector – Angola's single largest source of foreign capital, with more than $1bn channelled into the country since the beginning of 2007.

Last month, the trend was underlined when Portugal's state-owned Caixa Geral de Depositos signed an agreement to set up a new investment bank, which it will jointly own with Sonangol, Angola's state-owned oil group.