Financial markets will remain volatile for the foreseeable future, with the U.S. S&P 500 index today likely to fall another 20% as the U.S. Federal Reserve (Fed) continues to tighten monetary policy, according to JPMorgan Chase & Co (NYSE:JPM) chief executive Jamie Dimon.

Dimon couldn’t say when he thinks the market’s decline will hit, but noted that such a significant collapse in the S&P 500 Index is easy to imagine.

“It really depends on whether the landing is soft or hard, and since I don’t know the answer, it’s hard to say,” Dimon said in an interview with CNBC.

“The next 20% drop in the S&P 500 index bonds could be much more painful than the first one. Raising rates by another 100 basis points will be much more painful than the first 100 basis points, because people aren’t used to that,” he said.

According to the head of JPMorgan, Europe is already in recession, and a similar situation in the U.S. economy will come within “six to nine months,” with an economic downturn that could range from “very moderate to quite severe.

Ultimately, everything will depend on the consequences of the conflict in Ukraine, he added. Speaking about the economy and markets, Dimon said investors and companies should be prepared for a worst-case scenario. Companies should start strengthening their balance sheets immediately.

Earlier we reported that the Bank of England included inflationary government bonds in the list of bonds to be purchased.