Phone Answering Etiquette UK Phone Etiquette -- How Many Times Should The Phone Ring Before Hanging Up?

UK phone etiquette -- how many times should the phone ring before hanging up? - phone answering etiquette

Calling the UK from the United States, the phone rings twice as often as you here. In the United States, usually by phone after 4 machines Ring collected. I do not know if the people simply have no answer to machines in the UK, let, or whether the phone ring twice as often. I welcome to any idea of proper phone etiquette to London!