DVD rental chain Blockbuster has reported that Blu-ray titles are significantly outpacing HD-DVD at its stores. 

As a result the company is to expand the number of stores worldwide offering the Blu-ray format to 1,700 by the middle of next month.

Blockbuster will continue to offer Blu-ray and HD-DVD titles through its online rental service, and will offer both formats at its 250 stores that currently carry the two high-definition formats.

"We intend to meet the demands of our customers and we are expanding our Blu-ray inventory to ensure that our stores reflect the right level of products, " said Matthew Smith, senior vice president of merchandising at Blockbuster.

"While it is too early to say which high-definition format will become the industry standard, we will continue to closely monitor customer rental patterns at our stores and online so we can adjust our inventory mix accordingly."

Blu-ray and HD-DVD movies were introduced to the marketplace in 2006, and Blockbuster began offering all available high-definition formats through its online service as well as select titles in 250 stores in November 2006.

"Obviously, when customers are ready we can expand the Blu-ray offering into more stores and add HD-DVD to more locations if that is what customers tell us they want," added Smith.