The president-elect said he would not rule out the use of military force to seize control of the Panama Canal and Greenland.

President-elect Donald Trump on Tuesday said he would not rule out the use of military force to seize control of the Panama Canal and Greenland, as he declared U.S. control of both to be vital to American national security.

President-elect Donald J. Trump is expected to deliver an announcement about economic development on Tuesday at Mar-a-Lago, his Florida estate. Mr. Trump is also likely to answer reporters’ questions. He has given one news conference since winning the election in November.