Getting two different values for CurrentCulture in same solution

I have multiple projects in my solution: I have a WebApi project named "Api" that has a reference to a class library named "Models". I am setting the globalization information in my web config like this:

<globalization uiCulture="en"/>

I have some resources (.resx) files on my "Models" project and my problem is that I am getting the spanish version of the translated strings. If I debug and set a breakpoint in this line at the "Api" project:

var a = CultureInfo.CurrentCulture;

I am getting the value "en-GB", but if I set a similar line and breakpoint in the "Models" project, I get "es-Es". What I am doing wrong? How can I fix this? I would ideally keep the language configuration in my web config (since I have many transformations for multiple environments). Thank you very much