Republican presidential candidate Donald Trump speaks at a post Republican Convention campaign event in Cleveland, Ohio, July 22, 2016. [Photo/Agencies]

WASHINGTON - US Republican presidential nominee Donald Trump on Sunday threatened to pull the US out of the World Trade Organization (WTO) if his proposal on penalizing US companies for moving overseas is blocked.

Trump said in an interview with the NBC "Meet the Press" that he, if elected president, would impose a tax on US companies that shift production overseas then sell the products back to the US

"If they're going to fire all their people, move their plant to Mexico, build air conditioners, and think they're going to sell those air conditioners to the United States, there's going to be a tax," Trump told the NBC host Chuck Todd.

Trump said the tax rate could be 15 percent, 25 percent or 35 percent, and could be different for different companies.

When told that such tax would not get through the WTO, Trump said he would then renegotiate "or we're going to pull out."

"These trade deals are a disaster, Chuck. World Trade Organization is a disaster," the brash US billionaire said.

In the interview, Trump reiterated his support to the United Kingdom for its exit from the Europe Union, which he said he foresaw before it happened.

He said a fractured Europe is not necessarily bad for the US because the primary reason that European countries got together is to defeat the US on trade.

"I'm just saying, the reason that it got together was like a consortium so it could compete with the United States," Trump aid.

Asked about his previous remarks that the US protection of other NATO members should be conditional on their financial contribution, Trump firmly stood by his position.

"We have NATO and we have many countries that aren't paying for what they are supposed to be paying, which is already too little but they're not paying anyway," he said.

The countries Trump that mentioned that have to pay for the US protection included Japan, Germany, South Korea and Saudi Arabia.

"We're a different country today. We're much weaker. Our military is depleted. We owe tremendous amounts of money. We have to be reimbursed," Trump said.

"We can no longer be the stupid country," he added.