The automatically-triggered second round of sanctions supposed to start months ago as punishment for Russia's poisoning of former spy Sergei Skripal on British soil has yet to start, and the Trump administration shows no signs of imminent implementation.
Asked about the Skripal sanctions, the State Department told NBC News the U.S. "will proceed with our statutory requirements" but would not comment on when the sanctions will take effect.
"There is no deadline in the law for imposing sanctions," the State Department said, adding, "We intend to proceed according to the statutory requirements."
In a letter Thursday to Secretary of State Mike Pompeo, Sen. Bob Menendez of New Jersey, the top Democrat on the Senate Foreign Relations Committee, said he was "deeply concerned" and called the sanctions "more than two months overdue." Menendez said he expected the U.S. to "swiftly institute these additional sanctions against the Russian Federation, as required by law."
"The United States must not renege on our duty to stand with our allies against the Russian Federation and the international norms against chemical weapons," Menendez wrote.
The first round of sanctions came in August as mandated by the Chemical and Biological Weapons Control and Warfare Elimination Act of 1991.
Those sanctions cut off financing for some exports and licenses for selling sensitive national security goods to Russia. At the time, the State Department estimated the sanctions could cut off hundreds of millions of dollars in future exports.
Those sanctions also started a three-month clock for Russia to come into compliance with the law by providing "reliable assurances" that it won't use chemical weapons in the future and agreeing to "on-site inspections" by the United Nations. Under the law, a failure to meet that deadline triggers a second, harsher round of U.S. sanctions that could include downgrading diplomatic relations, suspending the state airline Aeroflot's ability to fly to the United States and cutting off nearly all exports and imports.
In early November, the administration told Congress that Russia was still violating the chemical weapons law. State Department spokeswoman Heather Nauert said at the time that "we intend to proceed" with more sanctions but did not offer a timeline.
Earlier this week, the European Union issued sanctions on the two Russian military intelligence officers identified as the poisoning suspects, as well as two of their bosses. Russia responded by warning of possible retaliation.
Skripal, a former Russian military officer convicted of spying for the U.K., was poisoned in March in Salisbury, England. Both he and his daughter, Yulia, were poisoned with the nerve agent Novichok, developed in the former Soviet Union. Both of them survived, but in June, two individuals a few miles away were exposed to Novichok in an incident police believe were linked, and one of those people died.
Moscow has adamantly denied involvement in either incident. In response to the new E.U. sanctions last week, the Kremlin said that the Russian officials targeted by the E.U. were "suspected groundlessly" and that Russia had yet to be presented with evidence against them.