Washington (AFP) - President-elect Donald Trump called Tuesday -- via Twitter -- for the cancellation of a multi-billion dollar Boeing contract to build the next Air Force One, calling the ballooning costs "ridiculous."

Converting a pair of 747-8 jumbo jets to state-of-the-art luxury command centers by 2024 had been estimated to cost $3 billion when Boeing was picked for the job in January 2015, but since then costs have apparently been rising.

"Boeing is building a brand new 747 Air Force One for future presidents, but costs are out of control, more than $4 billion. Cancel order!" Trump tweeted.

Speaking afterwards to reporters at Trump Tower, his Manhattan headquarters, the president-elect said: "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."

He said the estimated $4 billion cost was "totally out of control" and "ridiculous."

Trump has frequently singled out companies for criticism especially those planning to move jobs overseas, like Ford and Carrier. His latest attack-by-tweet came an hour after the Chicago Tribune posted an article including comments by Boeing's CEO expressing concern about the president-elect's protectionist bent.

Boeing chief Dennis Muilenburg said in a speech last week that trade is essential to the US economy and is a "large and growing percentage of our business," including aircraft orders from China, which accounts for a quarter of the firm's deliveries, according to the report.

But "anyone who paid attention to the recent campaigns and the election results realizes that one of the overarching themes was apprehension about free and fair trade," he was quoted as saying in the Chicago Tribune.

Trump has been critical of China for its trade policies and threatened to impose punitive tariffs on imports from the country unless US goods are granted better access to the huge Chinese market.

It was unclear if Trump, who according to a spokesman sold his Boeing shares in June, was aware of Muilenburg's comments before his outburst, but several US media were raising the possibility of a connection.

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"We don't know that Trump was responding to the Tribune story," wrote the Washington Post. "We do know that the last time he tweeted an out-of-the-blue opinion, about flag-burning, it was immediately after a Fox News segment showing students burning flags."

- Costs ballooning -

The legendary Air Force One jets -- light blue and white liveried, with "United States of America" emblazoned on the fuselage and an American flag on the tail -- are a powerful symbol of US might.

They are also equipped with numerous security and defensive measures, most of which are top secret.

The current double-decker 747-200s, first ordered by Ronald Reagan and put into service in 1990, are getting old. Earlier this year, the Air Force issued the first of a series of contracts for the project to build new ones.

Ironically, it was a $25.7 million effort to look at ways to cut the costs of fielding the next presidential aircraft. Instead, cost projections have apparently ballooned, prompting Trump's outburst.

In a statement, Boeing did not directly address Trump's comments or his cost estimate of $4 billion.

"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," it said.

"We look forward to working with the US 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 added.

Loren Thompson, a defense consultant, was quoted in news reports as saying that "Air Force One has unique communications, safety and self-protection features so that the president can function under the most trying circumstances - like nuclear war." The price tag, he said, "is driven by the demands of the mission."

High-ticket items like Air Force One have been targeted before because of spiralling costs. In 2009, President Barack Obama halted a project to replace the Marine One helicopters that ferry the president. Costs had soared to nearly $11.5 billion after the 28 helicopters were ordered in 2005.