A Ukrainian serviceman smokes as he guards an air base located in the village of Lyubimovka near a local airfield, southwest of Simferopol, Crimea's capital. REUTERS/Baz Ratner

Washington - The US military, eying ways to support allies during the crisis in Ukraine, is stepping up joint training through an aviation detachment in Poland and boosting participation in a NATO air policing mission, Defense Secretary Chuck Hagel told Congress on Wednesday.

Hagel said he aimed to speak with his Ukrainian counterpart on Wednesday and that the top US military officer, General Martin Dempsey, had spoken with his Russian counterpart earlier in the day.