President Obama warned the United Kingdom that it would face consequences on trade if leaves the European Union, saying the country would be in the “back of the queue” when it came to future trade agreements.

“I figured you might want to hear from the president of the United States what I think the United States is going to do,” Obama said during a press conference Obama with Cameron in London.

If the United Kingdom left the European Union, he suggested that there would likely be a new trade agreement with them, but warned that “it’s not going to happen anytime soon.”

“Our focus is in negotiating with a big block of the European Union to get a trade agreement done, and UK is going to be in the back of the queue,” he said. He added that U.S. negotiation with a “big market” of the European Union would help trade negotiations go smoother.

Obama added that the decision to exit would be made by the people of the United Kingdom.

“I’m not coming here to fix any votes,” he said. “I’m not casting a vote myself. I’m offering my opinion.”