Google on Friday slammed Microsoft in a blog post, accusing the rival company of backing proposals for tech giants to pay news publishers for content for self-serving purposes. 

We also believe that this important debate should be about the substance of the issue, and not derailed by naked corporate opportunism … which brings us to Microsofts sudden interest in this discussion, Googles senior vice president of global affairs, Kent Walker, wrote in a blog post. 

The post was published the morning of a House antitrust subcommittee hearing about the press. Microsoft president Brad Smith is set to testify at the hearing. 

Smith wrote a blog post last month urging the U.S. to adopt a policy similar to an Australian proposal that will force tech giants to pay publishers for content and subjects the tech companies to mandatory price arbitration if a deal cannot be reached. 

Google and Facebook pushed back on the Australian approach. Amid the contention, Microsoft boosted its search engine rival Bing as an option. 

Walker wrote that Microsofts self-serving claims were made in an effort to undercut a rival. 

Walker also questioned the timing of Microsofts push to embrace the policy proposals, noting it comes after Microsoft acknowledged its systems were exposed as part of what has become known as the SolarWinds hack. 

Its no coincidence that Microsofts newfound interest in attacking us comes on the heels of the SolarWinds attack, Walker wrote, adding that the attack exposed customers including government agencies, banks, hospitals and presumably news organizations. 

Microsoft was warned about the vulnerabilities in their system, knew they were being exploited, and are now doing damage control while their customers scramble to pick up the pieces from what has been dubbed the Great Email Robbery, he added. 

A Microsoft spokesperson was not immediately available for comment. 

On Friday, Google also further defended its role in distributing news content. 

Ahead of the hearing, a bipartisan group of U.S. lawmakers reintroduced the Journalism Preservation and Competition Act. The bill would establish a four-year safe harbor from antitrust laws for news outlets that would allow publishers to negotiate collectively with the tech platforms that distribute content, such as Google and Facebook. 

Walker wrote that Google welcomes the discussion of ways to create a better economic future for quality journalism, especially as the news media business model has been facing increased challenges for many years.

But proposals that would disrupt access to the open web (such as requiring payment for just showing links to websites) would hurt consumers, small businesses, and publishers, he added.

Thats why weve engaged constructively with publishers around the world on better solutions and will continue to do so.

It is not clear exactly where Google stands on the Congressional legislation reintroduced this week.

A spokesperson for Google said the comment refers to proposals such as Australias that would require news publishers to be paid just for showing links to their sites from a Google search, but the U.S. bill doesnt propose that.