EASA has published on March 17, 2022 a Safety Information Bulletin warning of the increased probability of problems with Global Navigation Satellite Systems (GNSS) in the current context of the Russian invasion of Ukraine:

https://ad.easa.europa.eu/ad/2022-02

The SIB proposes mitigation actions to be taken by the National Aviation Authorities, Air Navigation Service Providers and air operators to address the issue that spoofing and/or jamming has intensified in geographical areas surrounding the conflict zone and in other areas.