 The Office of Gas and Electricity Markets (Ofgem), the regulator of the electricity and gas markets in Great Britain, has launched an investigation into four of the largest British energy suppliers over suspicions that they not be complying with face-to-face and telephone sales regulations.
<clarity>  The Office of Gas and Electricity Markets (Ofgem), the regulator of the electricity and gas markets in Great Britain, has launched an investigation into four of the largest British energy suppliers over suspicions that they not be complying with face-to-face and telephone sales regulations.
 The Office of Gas and Electricity Markets (Ofgem), the regulator of the and markets in Great Britain, has launched an investigation into four of the largest British energy suppliers over suspicions that they not be complying with face-to-face and telephone sales regulations.