Amazon said Monday that a software update to improve the performance of Kindle Fire tablets will be released within two weeks.

The Seattle-based online retail titan sidestepped whether the upgrade was a response to complaints such as Internet browsing speed and wireless connection trouble that have arisen since the iPad challenger launched in mid-November.

Amazon did not released exact sales figures but said that it has sold millions of Fire tablets and that demand remained strong.

"Kindle Fire is the most successful product we've ever launched," Amazon said in an email response to an AFP inquiry.

"As with all of our products, we continue to make them better for customers with regular software updates," the statement continued.

"In fact, in less than two weeks, we're rolling out an over-the-air update to Kindle Fire that will improve performance, touch navigation, and give customers the option to choose what items display on the carousel."

Amazon has slashed prices of the Kindle e-readers and set a below-cost price for the Fire -- a rival of Apple's iPad -- with an eye at boosting sales of e-books, music and movies from its online store, analysts say.

"The Kindle Fire, at a retail price point of $199, is sold at a loss by Amazon, just as the basic Kindle is also sold at a loss at the current $79 retail price point," IHS iSuppli's Andrew Rassweiler said last month.

"Amazon makes its money not on Kindle hardware, but on the paid content and other products it plans to sell the consumer through the Kindle," Rassweiler said.