The lawsuit, the department said, does not seek to stop or restrict the publication or distribution of the book. Rather, the purpose is to "ensure that no funds are transferred to Snowden, or at his direction, while the court resolves the United States' claims," it said.
Snowden shocked the world in 2013 by revealing that the U.S. intelligence agencies utilized programs such as PRISM to conduct mass surveillance. Among those measures were the collections of phone and online communication records of the general public.
Snowden, now taking refuge in Russia and wanted by the United States, reportedly said that he would like to return to his home country, and that he wants fair trial.
"I would like to return to the United States. That is the ultimate goal. But if I'm going to spend the rest of my life in prison, the one bottom line demand that we have to agree to is that at least I get a fair trial," he said. "And that is the one thing the government has refused to guarantee because they won't provide access to what's called a public interest defense."