Fresh off securing the requisite number of delegates required to win the Republican nomination, the real estate mogul responded to comments by President Obama that he has heard from foreign leaders that the bombastic White House aspirant has them on edge.

“They’re rattled by him and for good reason,” Obama said at a press conference at the G-7 summit in Japan. “Because a lot of the proposals that he’s made display either ignorance of world affairs or a cavalier attitude or an interest in getting tweets and headlines instead of actually thinking through what is required to keep America safe.”

“That’s good. Is that right, is that good,” Trump told reporters at a press conference. “When you rattle someone that’s good.”

“If they are rattled in a friendly way that’s a good thing, not a bad thing,” he added.

Trump has turned heads among world leaders for advocating a policy of “America First” and for reducing the role of the U.S. in the world. Trump has advocated dramatically reducing the role of the U.S. in NATO and ending other mutual defense relationships unless other countries make larger payments for their security.

This week Trump repeated that Japan may need to seek out nuclear weapons of its own if it doesn’t pay the U.S. more for its safety. “I don’t want Japan to arm, but it’s possible if they don’t pay up they’re going to have to arm,” he said Tuesday in New Mexico. “Let them defend themselves,” he said of Japan and South Korea last month. “It’s time.”

Trump went on to criticize Obama for speaking out against him while overseas, seeming to invoke the principle that “politics stops at the water’s edge.”

“He is a man who shouldn’t really be airing his difficulties and airing what he’s airing where he is right now,” Trump said.

This article was originally published on Time.com.