What is the correct or received pronunciation of English?

This video gives some idea of the difference but there are many other local forms of speech

http://www.phon.ucl.ac.uk/home/wells/rphappened.htm

All I can say is that having many immigrants from Europe,Asia and Africa there is no longer such an emphasis on  what was once called BBC English.But it’s only on the last ten years we have heard reporters on the News with Lancashire accents.Indeed though mine has diminished I am still asked if  I am a foreigner.And working class people are not so willing to be told their speech is not right