The U.S. issued new sanctions Tuesday targeting Russian officials and businesses connected to the annexation of Crimea and support for separatists in the conflict in eastern Ukraine.

The move is especially notable as it comes just one month before President Barack Obama leaves office and President-elect Donald Trump — who has praised Russian President Vladimir Putin’s leadership — takes over.

And Secretary of State John Kerry’s potential successor, Trump nominee and ExxonMobil CEO Rex Tillerson, has openly expressed opposition to sanctions on Russia in the past and has drawn controversy for his business ties to the Russian President.

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Existing sanctions against Russia were issued by executive order and could be lifted by an incoming administration. But State Department Spokesperson John Kirby insisted the actions had “nothing to do with time on the clock.”

"It had to do with Russia's actions and it had to do with holding Russia accountable for what it’s for its violation of Ukrainian territorial integrity and sovereignty," said Kirby. "The next administration will obviously have to make their own decisions about this. We hope that they will come to see the wisdom in not conducting business as usual with Russia given their continued activities."

Moscow called the move "hostile," going so far as to threaten retaliatory action.

"We will be expanding our lists, we will see how we can respond asymmetrically. We reserve the right to choose the timing, the venue and form of counter-moves the way that will suit us, and the way it will be relevant to our own priorities in the American direction," Russian Deputy Foreign Minister Sergey Ryabkov said as reported by Russian News Agency Tass.

The statement issued by the U.S. Treasury announcing Tuesday’s sanctions said the targeting of seven Russian businessmen, eight companies and two vessels are part of a “continued effort to counter attempts to circumvent these sanctions.”

“As a result of today’s action, any property or interest in property of the designated persons in the possession or control of U.S. persons or within the United States must be blocked," the Treasury stated. "Additionally, transactions by U.S. persons involving these persons, or the vessels identified as blocked, are generally prohibited."

These latest measures add to a growing list of U.S. sanctions against Russia, first issued in 2014 after their annexation of the Crimean peninsula and expanded in response to continued support for separatists in eastern Ukraine.

The U.S. also expressed deep concern Tuesday over the recent spike in violence which led to the highest two-day casualty figure in the country since June of 2015. Six Ukrainian service members were killed and 33 wounded when Russian separatists attempted to seize additional Ukrainian territory.