[seanhunter]

I have been involved (from a Senior management perspective) in one significant layoff that affected US and UK employees. How we did it in that case is we took legal advice about what was the minimum requirement, and then leveled-up/adjusted from there to try to be as generous as we could. Layoffs are certainly possible even within the framework of EU labour law, but employees have more rights and depending on how big you are there may be additional requirements (eg in large companies in continental Europe I believe labour representatives have to be involved in the planning of the layoff etc).

The exact specifics of the deal in our case were a little different for US and UK folks because of things like how healthcare works in the US being so completely awful so you have to figure out things like COBRA which would just not be a thing in Europe. That forced us to adjust things to make it equitable/equivalent for both US and UK folks, but we really tried our best to be fair to everyone.

While the base requirements are much higher in the UK/Europe than in the US if you have teams in both places, you should do whatever you can to offer broadly the same deal to both teams. Besides your basic duty as a human to be fair to people, note that your remaining employees will judge you based on how you treated their departing colleagues.