She also said that turning back on globalisation will be a wrong approach.
"Yes and now, the economists would say," the Managing Director of the International Monetary Fund (IMF) said on whether middle class is in crisis.
"There is this crisis in the advanced economies," she added.
According to her, the middle class is both growing and shrinking -- growing on a global basis, but shrinking in countries like the US.
If there is excessive inequalities, it becomes difficult to achieve sustainable growth, she added.
Further, Lagarde said there was a large backlash from several economists including from her own institution when she first talked about inequality in 2013 here at Davos in a plenary session.
"If the policymakers do not listen now, I don't understand what can be done... There is no silver bullet response to excessive inequality," she said, adding that turning back on globalisation will be a wrong approach.
She also emphasised that policymakers must listen to the voters.
On concerns whether globalisation will take a hit due to the policies of incoming US President Donald Trump, she said, "We have very little by way of detailed information as to what the plan is if there is such thing as a plan."
She was speaking at a session at WEF Annual Meeting here on how to fix middle class crisis.
At the same session, eminent economist and Harvard Professor Larry Summers said wealthy feel they need to look after themselves while poor feel that they are not being heard.
He said globalisation itself has changed considerably today, while adding that one needs to be very cautious with adhoc policy making.
The panel also discussed whether poor employment prospects and low-income growth in many developed economies have laid the groundwork for the rise of populism. It also focused on whether policymakers ignored these trends or did too little to address them.
Besides, the panelists talked about what can be done to restore growth in the middle class and confidence in the future.
Speaking on the issue of middle class crisis, Ray Dalio, Bridgewater Associates, said populism is the number one issue in politics today.