America's foreign partners are worried that Donald Trump doesn't support U.S. alliances and that they would be in danger if he's elected president, Robert Hormats, vice chairman of Kissinger Associates, said Thursday.
Hormats has met with Chinese, Saudi and numerous other officials in recent days. The former assistant secretary of state said Trump's campaign trail rhetoric has left foreign leaders concerned.
The presumptive Republican presidential nominee has called for a readjustment of NATO, saying the alliance is "obsolete" and the United States pays too much under the current arrangement. He has also said it may be in America's favor if Japan, South Korea and Saudi Arabia obtain nuclear weapons.
U.S. allies now wonder whether Trump would leave them to fend for themselves, Hormats said.
"Great powers can't afford to be misunderstood because their allies have to calculate their futures based on the reliability of the American commitment," he told CNBC's "Squawk Box." "And our adversaries, if they think our commitment is weak or feckless, then they also think they can take liberties."
Hormats said it would be dangerous to pull back and replace U.S. support with nuclear weapons capability. He said he is hopeful Democrat Hillary Clinton will be elected president. Hormats called her "responsible and capable."
Overseas officials are also concerned that xenophobia and nationalism are on the rise in the United States, he added.
President Barack Obama also addressed foreign perceptions of Trump during a news conference in Japan on Thursday.
"They are not sure how seriously to take some of his pronouncements but they're rattled by him — and for good reason, because a lot of the proposals that he's made display either ignorance of world affairs or a cavalier attitude," Obama said.
Correction: Hormats made his comments Thursday. An earlier version misstated the day.