Global sales of BMW Group's core brand rose faster in June than at Audi and Mercedes-Benz as demand from China and the United States helped the premium carmaker to extend a lead over the two rivals in the first six months of the year.

Sales at the brand were up 9 percent last month to 153,075, the group said today, compared with growth of 5 percent to 140,300 and 8 percent to 131,609 at Audi and Mercedes respectively.

Six-month sales at BMW brand rose 8 percent to 804,000 cars, expanding the lead over runner-up Audi to 24,000 from 11,000 after five months. Half-year sales at Audi and Mercedes rose 6 percent each to 780,500 and 694,000 respectively.

"BMW has stronger momentum than Audi and Mercedes, that won't change in the second half," said Hanover-based NordLB analyst Frank Schwope. "Design of their cars has improved and they're ahead on fuel-saving technologies."