I can only speak to the UK where I have always been given a employment contract but it appears that something similar is a requirement in the EU

https://europa.eu/youreurope/business/human-resources/employ...

>When you hire staff, you should provide them with a written contract or an equivalent written statement confirming their working conditions

The fact it can be a statement rather than a contract may have an impact on the companies ability to change it at any given time without agreement from the employee, but I'm not an EU employment lawyer