Manufacturer beat off competition from BMW and Land Rover to land the award
Manufacturer sold 6,027 vehicles last month - meaning a year-to-date high of 43,205
Kia have sold 37,178 cars this year, while Mercedes-Benz have sold 53,686
GT treatment across their range could lead to huge sales boost
May saw an 8.3% sales increase on 2012, with year-to-date sales also record-breaking