The mood in the executive suites of German companies clouded over more than expected in September.

The Ifo business climate index fell to 84.3 points from 88.6 points in the previous month and thus to its lowest level since May 2020, as the Munich Ifo Institute announced on Monday in its survey of around 9000 executives.

Economists surveyed by the Reuters news agency had only expected a drop to 87 points.

"The German economy is slipping into recession," said Ifo President Clemens Fuest.

Those surveyed were even more skeptical about their business situation and prospects than they were recently.

Despite the consequences of the Ukraine war, the German economy still managed to achieve mini-growth of 0.1 percent in the spring.

At the moment, however, the prospects are bleak due to the worsening energy crisis and high inflation.

The Bundesbank expects the economy to shrink somewhat in the summer quarter that is coming to an end, and then even lose momentum noticeably at the end of 2022 and beginning of 2023.