Two United States Senators, Robert Menendez (NJ) and Chris Van Hollen (MD), wrote a letter dated August 13 to Secretary Pompeo in anticipation of his meeting with Greek Foreign Minister Nikos Dendias in Vienna on Friday, 

In the letter, the senators expressed their "grave concern" regarding Turkey's provocative actions in the Mediterranean over the past few days, according to The National Herald. They asked that Secretary Pompeo do three things:

1. "Call on Turkey to remove its ships from Greece's EEZ and to resolve this matter in accordance with international law."

2. "[I]mmediately begin to work with the European Union on a coordinated response to Turkey's increasing provocations and illegal actions in the Eastern Mediterranean."

3. "[F]ollow the law and impose sanctions on Turkey."

The letter concludes with the following paragraph: "The failure of the United States to act decisively at this critical time will only invite further Turkish escalation. Therefore, we urge you [to] take all appropriate measures to ensure Turkey removes its naval vessels from Greece's EEZ and adheres to its international obligations."