President-elect Donald Trump wants the government to cancel the purchase of Boeing’s new Air Force One plane, saying it is “ridiculous” and too expensive.

But his loose tweeting saw the value of the American company plummet, and he quickly came under fire for getting his figures wrong.

The tweet came just minutes after Boeing criticised the president–elect for his trade policies, in a Chicago Tribune article.

“Boeing is building a brand new 747 Air Force One for future presidents, but costs are out of control, more than $US4 billion ($A5.4 billion). Cancel order!” said Mr Trump on Twitter on Tuesday.

Pres.-elect Trump on Boeing Air Force One contract: "The plane is totally out of control." https://t.co/wCUahNube6 https://t.co/5eZXPX5Gub

— ABC News (@ABC) December 6, 2016

Speaking shortly afterward to reporters in New York, Mr Trump said: “The plane is totally out of control. I think it’s ridiculous. I think Boeing is doing a little bit of a number.”

“We want Boeing to make a lot of money but not that much money,” added Mr Trump, who takes office on January 20.

Boeing has issued a statement on its contract contradicting his figures:

“We are currently under contract for $170 million to help determine the capabilities of these complex military aircraft that serve the unique requirements of the President of the United States. We look forward to working with the U.S. Air Force on subsequent phases of the program allowing us to deliver the best planes for the President at the best value for the American taxpayer.”

Boeing’s shares fell sharply in the wake of Mr Trump’s tweet, and the irony of its effect is that it may well cost American manufacturing jobs.

Trump’s tweet cost Boeing shareholders more than $550 million: https://t.co/RlpWodamMY pic.twitter.com/lrtYPrMpzi

— MarketWatch (@MarketWatch) December 6, 2016

If you're a Boeing employee who voted for Trump, you must feel pretty stupid right now.

/Air Force One/

— imfabulous (@imfabulous13) December 6, 2016

The White House says statistics cited by Donald Trump on Air Force One costs “do not appear to reflect arrangements” between Boeing and the Department of Defence.

The Air Force first announced in January 2015 that Boeing’s 747-8 would be used to replace the two current Air Force planes used to transport the US president.

Air Force One is one of the most visible symbols of the United States.

Details about the total value of the new contract have not been released, but the Air Force has previously said that it had earmarked $US1.65 billion for two replacement jets.

The US Air Force awarded Boeing Co an initial contract worth $US25.8 million in January.

US presidents have used Boeing plane’s since 1943, according to the company’s website.

The 747-8 planes, 73 metres long with a wing span of 68 metres, can fly direct from Washington to Hong Kong, 1600 km farther than the current Air Force One.

Some commentators are suggesting Mr Trump has an ulterior motive for his outrage against Boeing, which donated nearly a million dollars to the Clinton Foundation before the election.

Trump is priv citizen. $4 bill, Air Force One falsehood cratered Boeing stock. He "sold" shares in June. Shareholders can sue him 4 fraud.

— Kurt Eichenwald (@kurteichenwald) December 6, 2016