Not an expert, exactly, but my understanding is that the U.K. does not have an expressly documented “right to free speech” in the same way that the US does, and as such there are more prohibitions than we are used to. For example, you can get a court order not to speak about a civil suit under threat of jail in the U.K. In the US, this isn’t typically a crime, but a civil matter. You can say what you want, but there can be civil consequences.
Also, I know the U.K. is not always great for press freedoms. I remember when the government forced the Guardian to destroy its hard drives during the NSA reporting.