China cheating US with currency manipulation: Trump

China is making a fortune with currency manipulation, Republican presidential nominee Donald Trump has alleged, saying if he is elected as president, he would impose a 10 per cent tax on Chinese products in the United States markets.

"China makes a fortune with currency manipulation. It's cheating. It's cheating," Trump said in Columbus, Ohio.

"When I sit down and say, listen, you've got to stop this, you're killing us, you've got $500 billion trade deficits for us, you got to stop it, we have rebuilt China," he said.

"And when I tell them this, and when I say, listen, you got to do it, you got to do it see, we have all the power, but nobody knows it," Trump said at the election meeting.

He further added if caught doing the same, ten per cent tax will be levied on each goods coming from China.

"And if they (China) don't, we collect ten per cent, we make a fortune. But they're going to stop cheating," he added.

Taking a dig at Obama administration, Trump said, "There's nobody that tells them this. When they come over, President Obama puts a tent on the White House lawn, right, and they give them a steak dinner like you've never seen before," Trump said.

He said several states have suffered because of trade deals and Ohio has lost one in three manufacturing jobs since Bill Clinton signed NAFTA which put China into the World Trade Organisation.

"Hillary rammed through the job killing trade deal with South Korea, that's been a killer," Trump said.