Twitter is suing the US government over restrictions on what it can say publicly about the surveillance of its users.

The California company argues that government censorship of its full Transparency Report is a violation of its right to free speech as stated in the US constitution.

In its filing, Twitter said that the government "engages in extensive but incomplete speech about the scope of its national security surveillance activities."

In the summer, Twitter published its fifth Transparency Report but pointed out in a blog post at the time that it is legally unable to include information pertaining to national security requests.

In a blog post explaining the lawsuit, Twitter Vice President Ben Lee said: "It's our belief that we are entitled under the First Amendment to respond to our users' concerns and to the statements of U.S. government officials by providing information about the scope of U.S. government surveillance."

"So, today, we have filed a lawsuit in federal court seeking to publish our full Transparency Report, and asking the court to declare these restrictions on our ability to speak about government surveillance as unconstitutional under the First Amendment."

With this lawsuit, Twitter hopes to be given provision to more fully inform its usership of the extent to which US authorities are accessing its data.

The issue of governmental oversight has become particularly pronounced since the NSA/Edward Snowden scandal last year that revealed how US government agencies were pillaging the databases of major tech firms, including Twitter.

Last month it was revealed that the government had threatened Yahoo with a $250,000 a day fine until it consented and cooperated with its investigation.

The US Department of Justice has yet to comment on the lawsuit.