The Pentagon is pressing for a national security exemption for sanctions on countries purchasing Russian military hardware but which are also U.S. allies.

Under the current sanctions law against Russia, American allies—and countries Washington is courting—such as Turkey and India could face penalties for purchasing weapons from Moscow. The imposition of those sanctions could torpedo budding relationships such as the one between Washington and New Delhi and threatens to unravel the alliance with Turkey.

“Look, the question is, there was a law passed, it did not a have a national security waiver that said if a country buys significant Russian equipment, I forget the specific wording, then we could not sell any of our equipment there,” Defense Secretary James Mattis told reporters at the Pentagon on April 30.  “And I asked that a national security waiver authority be given to the secretary of state, not to me, so that there would also be an internal control over what I think ought to be done. I would have to go across the river and I'd have to make the argument there.”

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Mattis said that the United States should not box itself into a rigid process that could backfire on Washington. “I think that's a health way to set it up to carry out the spirit of the Congress without finding ourselves basically painting ourselves into a corner,” Mattis said. “I don't want to say which countries we would use or where we would we use, because there's a multitude of factors, where I could make a criteria and then I would violate that criteria because of the specific each country would be an individual case.  So I really don't want to even speculate on that.”

However, while Mattis is making the case for exemptions, newly installed Secretary of State Mike Pompeo is working to deter Turkey from buying the Russian S-400 air defense system. "The secretary [Pompeo] underscored the seriousness of U.S. concerns...if [the Turkish authorities] go ahead," a senior U.S. State Department official told reporters in Brussels. "He asked Cavusoglu to closely consider NATO interoperable systems."

Pompeo warned the Turks that the Ankara could face sanctions if it when through with the deal. The Turks, however, seem to be undeterred—and struck a defiant tone about the potential infringement upon its sovereignty. “The ‘I will impose sanctions if you buy’ approach will not affect Turkey. Turkey will not accept this. If we are going to discuss what we can do together in the future, we are in,” Turkish Foreign Minister Mevlut Cavusoglu told reporters.

Dave Majumdar is the defense editor for the National Interest. You can follow him on Twitter: @davemajumdar.

Image: Reuters.