WASHINGTON, Nov 19, 2008 (AFP) - Microsoft has announced plans to offer free anti-virus software to PC users starting next year.

The Redmond, Washington-based software giant said the software, code-named "Morro," will "provide comprehensive protection from malware including viruses, spyware, rootkits and trojans."

In a statement on Tuesday, Microsoft said Morro would be focused on "core anti-malware protection" and would be available in the second half of 2009.

"This new solution, to be offered at no charge to consumers, will be architected for a smaller footprint that will use fewer computing resources, making it ideal for low-bandwidth scenarios or less powerful PCs," it said.

Microsoft said it will discontinue sales of its current software security program, Windows Live OneCare, from June 30, 2009.

"Customers around the world have told us that they need comprehensive, ongoing protection from new and existing threats, and we take that concern seriously," said Amy Barzdukas, senior director of product management for the Online Services and Windows Division at Microsoft.

"This new, no-cost offering will give us the ability to protect an even greater number of consumers, especially in markets where the growth of new PC purchases is outpaced only by the growth of malware."

Microsoft said "Morro" will be available as a download and offer malware protection for Windows XP, Windows Vista and Windows 7 operating systems.

A number of companies are in the business of selling software security programs and industry analysts said Microsoft's move to provide free security software could pose a challenge to such firms as McAfee and Symantec.