Amazon will allow purchasers of its new Kindle Fire tablets to pay $15 extra to turn off advertisements that are built into the devices.

The move comes after criticism of the company mounted after reports that the company would not allow buyers to pay to block the ads, as it had done with earlier tablets.

Amazon on Thursday unveiled larger Kindle Fire tablets. The company has initially had said the tablets would come with ads or "special offers".

Amazon's new wireless tablets have not yest been approved by the Federal Communications Commission. The company said it expects to receive the approval bnefore the planned shipping date of November 20.