Google and its partner Onix are suing the U.S. Department of the Interior for taking bids only from Microsoft resellers to replace its e-mail software system.

The lawsuit was reported Monday by the blog Tech Dirt, which also posted the complaint. Google confirmed the suit and that the complaint. Onix is a Google reseller based in Westlake, Ohio.

The Interior Department was seekling bids to consolidate its e-mail system for 88,000 users in a five-year contract worth $59 million, according to the complaint. Google says in the court document that the department specified it would take bids only for Microsoft's Business Productivity Online Suite (which Microsoft has since rebranded Office 365). Google said in the document that it met with department representatives and said that its product, Google Apps, could provide the same technology as Microsoft's.

In the lawsuit, Google said Interior responded that it did not believe Google could meet the department's security requirements.

The Mountain View, Calif., search giant claims the department violated its competition rules in government contracting and arbitrarily chose an e-mail system.

“Google is a proponent of open competition on the Internet and in the technology sector in general," the company said in a statement released today. "Here, a fair and open process could save U.S. taxpayers tens of millions of dollars and result in better services. We’re asking the Department of Interior to allow for a true competition when selecting its technology providers.”

The competition to sell e-mail as a cloud service is heating up between Microsoft and Google. Microsoft recently announcing New York City, the state of California and the state of Minnesota as customers for Office 365.

Microsoft declined to comment on the lawsuit. Interior officials did not immediately respond to a request for comment.

Update 5:49 p.m.: The Department of Interior said they are not commenting on the lawsuit.