Trump won't rule out using U.S. military to control Panama Canal or Greenland

President-elect Donald Trump on Tuesday declined to rule out using the U.S. military to take control of the Panama Canal and Greenland, expanding on a spate of recent remarks he has made about acquiring more territory for the United States during his second term.

"We need them for economic security," Trump said of both the Central American trade route and the autonomous territory of Denmark, during a lengthy press conference at his Florida home, Mar-a-Lago.

A reporter asked Trump if he could assure the public that he would not use military or economic coercion in pursuit of either land.

"No, I can't assure you of either of those two," the president-elect replied.

"The Panama Canal was built for our military. I'm not going to commit to that, no ... It might be that you'll have to do something," he said.

Trump also expressed concern and frustration about China's activity in both the Panama Canal and Greenland, sending a possible signal to the powerful U.S. adversary about its own efforts to extend its global reach.

The canal is "being operated by China," he said. "We didn't give it to China, and they've abused it."

At the same press conference, Trump announced that his administration would seek to change the name of the Gulf of Mexico to the "Gulf of America."

"What a beautiful name. And it's appropriate," he said.

The petroleum rich body of water is the world's ninth largest, and has been identified on maps as the Gulf of Mexico since the 1500's.

Since winning the November presidential election, Trump has repeatedly mused about annexing territories, especially the Panama Canal. He has criticized former President Jimmy Carter, who died on Dec. 29, for negotiating the treaty that ultimately gave Panama full control of the 51-mile