Unstable loans and escalating levels of global debt could plunge the world into another financial crisis, departing German Finance Minister Wolfgang Schaeuble told the Financial Times in an interview published Sunday.

"Economists all over the world are concerned about the increased risks arising from the accumulation of more and more liquidity and the growth of public and private debt ... I myself am concerned about this, too," he said.

Schaeuble, who is poised to become speaker of the Bundestag in Germany's new government, warned that "new bubbles" could soon emerge after central banks pumped trillions of dollars into financial markets.