U.S. President Donald Trump’s insistence that he wants to have the Panama Canal back under U.S. control is feeding nationalist sentiment and worry in Panama, home to the critical trade route and a country familiar with U.

Russia’s foreign ministry has called on Trump to reaffirm the current international agreement surrounding the Panama Canal and to leave it in control of the nation of Panama.

In recent weeks, when he was President-elect Donald Trump publicly said that Panama should return the Panama Canal to the United States, and he would not rule out using military force to reclaim it. At his presidential Inauguration on Monday Trump doubled down on saying that his new administration was going to take back the canal.