"Resurgence of great power competition is our principal security challenge. And we see the effects of that competition throughout the (Middle East) region. Russia's support for the Assad regime is not only propping them up but it is also adding complexity to the defeat IS [Daesh*] campaign," Votel told the Senate Armed Services Committee.
Votel also accused Russia of trying to manipulate the situation in Syria, saying this puts the anti-Daesh campaign's progress at risk.
The US administration presented a new national defense strategy earlier this year. The document considers great power competition Washington's primary focus in national security.
*Daesh (also known as ISIS/ISIL/IS) is a terrorist group banned in Russia