The reunited Spice Girls are expanding their upcoming world tour to cater for "overwhelming demand" for tickets.

An extra three dates have been tacked onto the tour, bringing the total to 14 performances across nine countries. Vancouver will now host the first concert, on Dec. 2, followed by a new date in San Jose on Dec. 4. A Shanghai performance has been added for Jan. 10, 2008, while the Beijing gig intended for that night has been moved forward to Jan. 8, 2008.

Representatives for the five-piece pop band today said three million fans had registered for tickets to the tour in just the three weeks to July 19. Each of those registrations enables the gig-goer to purchase six tickets, which equates to potential interest for 18 million concert tickets.

Fans can vote their hometown onto the tour through the new Spice City feature, which was launched this week on the official Spice Girls Web site.