Kasich takes thinly-veiled swipe at Trump amid growing tensions

Gov. John Kasich has been notably absent from the main events at the Republican National Convention being held in his home state of Ohio this week, and on Tuesday he took a thinly-veiled swipe at the presumptive nominee.

Kasich seemed to offer a rebuttal of Donald Trump's campaign, rejecting what he called a "stew" of nationalism, isolationism, and anti-trade sentiments.

"What does that stew look like? What does that mean for the world? What does it mean for stability, for peace, for relationships? I'm very concerned about it," the Ohio governor said during an address for the International Republican Institute.

The remarks at the event came only a day after the Trump campaign lashed out at Kasich for his refusal to play a big role in the convention in his backyard.

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"He's embarrassing his party in Ohio," Trump campaign chairman Paul Manafort said Monday. He accused Kasich of making a politically calculated decision designed to help his own presidential chances someday.

Kasich is one of only a handful of rivals who has not agreed to join the primetime convention speakers list, which both Ted Cruz and Marco Rubio agreed to join. He instead remained subtly critical of Trump's campaign direction during Tuesday's event.

See some of the other politicians shying away from the convention:

"There is an increasing tide of isolationism; Let's just take care of us, let's just pull the shades down, lock the doors and forget the rest of the world, we'll just take care of ourselves," Kasich said. "I am very worried about it."

While the Ohio governor didn't name Trump, he also discussed the rising movement urging the United States to leave NATO, a sentiment that presumptive Republican presidential nominee has suggested at certain points during the campaign.

"We think NATO doesn't matter? Are you kidding?" Kasich rebutted. "What would we replace it with? Are we supposed to tell everyone they are on their own?"

Kasich also weighed in on the recent vote for Britain to leave the EU, saying the big winner of the vote may have been Russia.

"The guy who was the happiest about Brexit was Putin," said Kasich.