President Donald Trump said that the United States will take back the Panama Canal or “something very powerful is going to happen.”

After departing Air Force One at Joint Andrews Airbase, the president confirmed his seriousness to either take back the canal or get a new deal, arguing that China is controlling the waterway and using it against the United States.

“Very happy people right now. Nobody thought that was going to happen. So they are home, they’re safe with their families. That was a big one. Secretary of State Rubio is in Panama right now, and we’re talking about the Panama Canal. What they’ve done is terrible. They violated the agreement. They’re not allowed to violate the agreement. China is running the Panama Canal. It was not given to China, it was given to Panama, foolishly. But they violated the agreement and we’re going to take it back or something very powerful is going to happen. And as far as other things are concerned, as you know, we had a very busy week,” Trump told reporters.

Secretary of State Marco Rubio visited Panama over the weekend and warned the leaders that the United States would retaliate if they did not act quickly to limit China’s influence over the canal. Then, Trump told reporters that if the United States is not granted control of the canal, “something very powerful is going to happen.”

The president has previously hinted at the possibility of applying military and economic pressure to get Panama to cede the canal.