Defense Secretary Ash Carter is summoning top U.S. defense and diplomatic officials to Germany to assess the effectiveness of NATO's strategy toward Moscow in response to the Ukraine crisis.
About two dozen generals and diplomats will discuss privately on June 5 whether the political will is still in place in Europe to maintain sanctions on Russia.
While they will also discuss military options, including directly arming Ukraine, Carter "believes very strongly that the economic sanctions are the most important part of putting leverage on Russia right now," one official told dpa.
Carter admitted on June 3 that so far the sanctions have not had the desired effect.
"We have to take another look at what we are doing here," he told troops in Stuttgart, descrying the "sad turn" taken by Russia in the last year.
The meeting comes as a major battle erupted in eastern Ukraine, breaking the fragile February cease-fire agreement.
Based on reporting by Reuters, AP, and dpa