Israel's first F-35 stealth fighters were due to arrive in the country several hours late Monday, as US President-elect Donald Trump blasted "out of control" costs for the warplane programme.

The first two of 50 F-35s to be purchased by Israel from US aerospace giant Lockheed Martin were due to arrive at Nevatim air base in the country's south around 7:30 pm (1730 GMT), more than five hours late after they were delayed by bad weather in Italy.

As US Defence Secretary Ashton Carter was in Israel to mark the delivery, Trump lashed out on Twitter against the fighter jet programme.

"The F-35 program and cost is out of control. Billions of dollars can and will be saved on military (and other) purchases after January 20th," Trump said, referring to his inauguration day.

Speaking at the landing site in southern Israel, Jeff Babione, Lockheed's programme manager for the F-35s, told journalists the firm was confident that the planes represented a good deal.

"It's great value and I look forward to any questions that the president-elect may have," he said.

With a current development and acquisition price tag of $379 billion for a total of 2,443 F-35 aircraft -- most of them destined for the US Air Force -- the plane is the most expensive in history.

Once servicing and maintenance costs are factored in over the aircraft's lifespan through 2070, overall program costs are expected to soar to $1.5 trillion.

The row and the long delay in the fighters' arrival threatened to overshadow what Israel had labelled a key day in its military's future.

- Israeli 'aerial superiority' -

Defence Minister Avigdor Lieberman said in a statement beforehand that the "the F-35 constitutes another element allowing us to maintain our aerial superiority in the region."

While other countries have ordered the planes, Israel -- which receives more than $3 billion a year in US defence aid -- says it will be the first outside the United States with an operational F-35 squadron.

Carter and Lieberman were to be joined by Israeli Prime Minister Benjamin Netanyahu for the ceremony.

However the two planes' takeoff from Italy was delayed by five hours due to fog there.

"In accordance with American safety regulations, the Adir takeoff is delayed," a military official said at the landing site in southern Israel, using the word meaning "mighty" by which the plane has been designated in Hebrew.

A Lockheed official said the delay was caused by Italian air safety regulations, rather than any limitation of the planes.

Some 4,000 people had been expected to watch the landings in southern Israel but as the sun went down the crowds had thinned and thousands of white chairs sat empty in front of a stage.

Israel is buying its first 33 F-35s at an average price of about $110 million (103.5 million euros) each.

It will be receiving the F-35A model for standard takeoff and landings. The B and C models are for short takeoffs and aircraft carriers.

Israeli components will be integrated in the plane, which will be known as the F-35I.

- Supersonic stealth -

Among the aircraft's main features are advanced stealth capabilities to help pilots evade sophisticated missile systems.

The single-pilot jets can carry an array of weapons and travel at a supersonic speed of Mach 1.6, or around 1,200 miles per hour (1,900 kilometres per hour).

The ultra-high-tech helmets, at a cost of some $400,000 each, sound like something out of a science fiction film.

The helmet includes its own operating system, with data that appears on the visor and is also shared elsewhere.

Thermal and night vision as well as 360-degree views are possible with cameras mounted on the plane.

In Israel, the planes, designed for multiple combat situations, will initially replace a group of ageing F-16s.

They are seen as helping the country maintain its edge in the Middle East, particularly as its main enemy Iran seeks further influence in the region.

Israel is especially concerned over whether Iran will seek to develop nuclear weapons by violating the international accord it has signed with world powers.

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LOCKHEED MARTIN