The Chester-born centre-back played in Welsh schoolboy sides having been raised in Flintshire but once he left education there was no provision for him to continue in that national set-up.
FIFA changed the rules in 2009 to allow anyone with five years of compulsory education in the specified country to be eligible to represent that nation.
But by then the 23-year-old had already made his mind up about playing for England and although he has yet to represent his country despite being named in Fabio Capello's squads he remains determined to make the breakthrough.
"I've not considered Wales. I have spoken to Gary Speed a couple of times and made my plans clear," Shawcross told BBC Sport.
"He is a very good, young manager and I have a lot of respect for him.
"But I made my decision a long time ago when the current rule wasn't in place that I could play for Wales.
"Obviously he wants me to play for Wales but I made a decision and I'm going to stick with it.
"Hopefully I can prove I am good enough to get into the England team.
"I'm not at the moment so I don't think I'm too wanted there.
"It is tough to get in as there are a lot of world-class players in my position.
"It is good Wales want me but this rule wasn't in place when I made my decision.
"My decision might have been different if the current rule was in place at the time but these things happen."