The article linked to this seems to suggest that Covid-19 is the cause for these excess deaths.

Statistics on excess deaths provide information about the burden of mortality potentially related to the COVID-19 pandemic, thereby covering not only deaths that are directly attributed to the virus but also those indirectly related to it. In addition to confirmed deaths, excess mortality captures COVID-19 deaths that were not correctly diagnosed and reported, as well as deaths from other causes that may be attributed to the overall crisis situation.

The article linked to this seems to suggest that Covid-19 is the cause for these excess deaths.