Republican presidential nominee Donald Trump said Tuesday that voters will see a "mass exodus of manufacturing" to America from South Korea, China and other countries if they vote for him in November, as he stepped up efforts to court swing voters in a battleground state.

Trump made the remarks during a campaign speech on tax policy in Savannah, Georgia, as various polls have shown the former president and his Democratic rival, Kamala Harris, in a tight race with the general election less than six weeks away.

"Vote for Trump, and you will see a mass exodus of manufacturing from China to Pennsylvania, from Korea to North Carolina, from Germany to right here in Georgia," he said. "They're going to come to Georgia from Germany and other places."

Trump also said that if reelected, he would task a "manufacturing" ambassador with carrying out "pro-manufacturing" policies.

"I will appoint a manufacturing ambassador whose sole task -- and it'll be a great one -- will be to go around the world and convince major manufacturers to pack up and move back to America," he said.

He mounted an attack on Harris, calling her a "tax queen" and accusing her of seeking the "largest capital gains tax" in the history of America.

"It's called an unrealized capital gain. That means that you're going to pay a capital gain even if you haven't realized it," he said.

Policymakers from South Korea and other countries have been carefully watching presidential candidates' remarks on the campaign trail as a presidential transition in Washington might affect America's policy on trade, diplomacy and other areas. (Yonhap)