Central banks not finishing what they have started in bringing inflation back to Earth would be the “greatest tragedy” for the global economy, according to former U.S. Treasury Secretary Larry Summers.

Central banks around the world have tightened monetary policy aggressively over the past year in a bid to get inflation under control, with annual consumer price increases running at multi-decade or even record highs across most major economies.

Economists are turning cautiously optimistic as recent data has suggested a slowdown in inflation, which may enable policymakers to ease and eventually stop their aggressive cycle of interest rate hikes.

Speaking on a CNBC-moderated panel at the conclusion of the World Economic Forum in Davos, Switzerland, on Friday, Summers said economists and business leaders at the summit were experiencing an “exhilaration of relief” but cautioned policymakers against resting on their laurels.