WASHINGTON (Reuters) - Three gun control advocacy groups are banding together to try to block the Trump administration from allowing Americans to access blueprints for 3-D printable guns on the internet.

In a July 24 letter to a federal judge in Texas seen by Reuters, the groups said they would seek an injunction to block a company called Defense Distributed from publishing schematic designs for the guns online.

Such postings on the internet have the potential to allow anyone, equipped with a readily accessible 3-D printer, to make their own firearm.

Tuesday’s letter was signed by the Brady Center to Prevent Gun Violence, Everytown for Gun Safety and the Giffords Law Center to Prevent Gun Violence.

At issue is a June settlement between Defense Distributed and the U.S. State Department that allows the company to legally publish gun blueprints online, something its website says it plans to do by Aug. 1.

The settlement could “enable terrorists, organized crime syndicates, felons [and] domestic abusers all to get quick, easy access to untraceable guns,” said Nick Suplina, managing director of law and policy for Everytown.

Neither the company nor its lawyer immediately replied to a request for comment.

Under the Obama administration, the State Department forced Defense Distributed’s founder, Cody Wilson, to remove online gun instructions posted earlier, arguing that they posed a national security risk and violated the International Traffic in Arms Regulations.

Wilson fought the State Department by filing a lawsuit in the U.S. District Court for the District of Western Texas in 2015, saying the government was violating free speech and the right to bear arms guaranteed in the U.S. Constitution.

Since then, the government has prevailed in court, winning at trial and later on appeal. As recently as April, President Donald Trump’s Justice Department was still asking the judge to dismiss Wilson’s lawsuit.

Critics say there has been no explanation for the June settlement and the administration’s abrupt reversal on the issue.

“For some unknown reason, having won every step of the way the government did a 180,” said Brady Center co-president Avery Gardiner.

According to terms of the settlement posted online, in addition to letting the company publish its blueprints, the government agreed to pay Defense Distributed nearly $40,000.

A State Department spokesman said the settlement was voluntarily entered into by both parties.

Under proposed new rules, the State Department will relinquish regulatory oversight over exports of firearms and transfer that authority to the U.S. Commerce Department.