(CNN) The US State Department is continuing to punt on its congressionally mandated obligations to hold Russia accountable for poisoning an ex-spy in the United Kingdom, and despite its continued insistence that it would consult with Congress on the matter, multiple Hill sources tell CNN no such consultations have occurred.

"State's consultations thus far have been acknowledging that they're now well past the deadline and telling us they're working on it," a senior Democratic Hill aide said. A senior Senate staffer said that "there has been zero" engagement with Congress on the issue beyond the notification in November that Russia had failed to certify that it was not using chemical weapons. That announcement was meant to be accompanied by at least an announcement of a second round of sanctions -- but three months, later they have not been imposed.

Sen. Jeanne Shaheen, a New Hampshire Democrat on the Senate Foreign Relations Committee, criticized the administration's inaction.

"Too often, the Trump administration resorts to foot dragging when it comes to holding foreign powers accountable, particularly Russia," Shaheen told CNN Wednesday. "The Kremlin used a nerve agent on NATO soil -- it's hard to overstate how brazen this behavior is. There's overwhelming bipartisan agreement that the Kremlin should pay a heavy price and the law is crystal clear in this respect. It's time for some follow through."

Once the US determined that the Russian government was behind the poisoning of Sergei Skripal with VX nerve agent last March, an attack that also affected Skripal's daughter and others, the US responded with sanctions on certain technology, required under the Chemical and Biological Weapons Control and Warfare Elimination Act of 1991.

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