The Abu Dhabi investment fund with the biggest stake in Mercedes-Benz said Sunday that it has spent $328 million for a piece of a Brazilian bank recently floated by Spanish financial giant Banco Santander.

Aabar Investments’ deal – the latest in a string of big bets by the fund this year – is another sign that Gulf governments are regaining their appetite for fresh investments and have plenty of cash left to spend despite the economic downturn.