The global economy is enjoying a Goldilocks moment, with growth and inflation neither too hot nor too cold.

But a decade after the collapse of the US subprime mortgage market triggered a global crisis, there are warnings that debt is becoming a big risk, lurking in the next room like the scary bears in the children's tale.

The outlook for the global economy appears bright for the moment thanks to steady growth in the world's major economies, in stark contrast to reigning pessimism only a year ago when Britain's Brexit vote and Donald Trump's protectionist policies weighed on sentiment.

The US economy is purring along in the longest cycle of expansion in its history and China, the locomotive of global growth in recent decades, is on track to deliver more.