If I were to say「イギリス」or「イギリス人」to a native speaker. What would they understand that to mean?

I've read multiple conflicting reports online about the meaning of イギリス (Igirisu) on various language learning forums.

Some say that people would always understand it to mean "British", but others say only most will understand it as "British" but some will think it means "English". Then some will say that only in the past people would assume it to mean "English" rather than British.

If I were to meet someone on the street right now, and introduce myself as 「イギリス人」, What would they take it to mean? Is there one answer? Does it depend on the person? Maybe it would even differ depending on dialect / prefecture?

In the end, is it just easier to specify further? (Ie. use English, Scottish, N.Irish or Welsh in it's place) Or would that come off as weird?