A major ceremony celebrating the arrival of two cutting-edge F-35 stealth jets intended to demonstrate the bond between the United States and Israel was delayed by several hours Monday due to their inability to take off in bad weather.

US Secretary of Defense Ash Carter welcomed the delivery of two F-35 fighter aircraft to Israel, making it the first country outside the United States to receive the advance aircraft.

“There’s no better symbol of the US commitment to Israel’s security than the F-35, the most capable aircraft in the skies,” Carter declared. 

Israeli Prime Minister Binyamin Netanyahu and Israeli President Reuven Rivlin also attended.

“The plane that will land here will change the rules of the game,” Rivlin said at the ceremony. “In our region you cannot be second.”

But bad weather in Italy delayed the multimillion-dollar planes by more than six hours before the two planes eventually touched down.

The postponement was announced minutes before President-elect Donald Trump sent a tweet slamming the F-35.

“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 tweeted, referring to Inauguration Day.

The jet has been labeled the most expensive weapons program in history, with some estimates placing its cost at $400 billion.

Its development has been beset by delays and cost overruns, making it the subject of intense criticism. The chairman of the Senate Armed Services Committee, Arizona Republican John McCain, labeled the development of the weapons system a “scandal and a tragedy.”

Trump’s tweet plunged the stock price of the plane’s manufacturer, Lockheed Martin, into free fall.

But the F-35’s proponents say international orders for the aircraft will help drive the price per aircraft – currently well over $100 million – down, as they will allow the manufacturer to achieve economies of scale.

Israel’s decision to acquire 50 of the aircraft represents a welcome development for the jet’s backers, as some countries have recently abandoned plans to introduce it into their respective air forces. Canadian Prime Minister Justin Trudeau recently opted to buy older model F/A-18s instead.

Military analysts in Israel welcomed the aircraft’s delivery, noting its symbolism.

“The idea that you’re the first state, the first air force in the area that gets it, it’s a lot to your reputation,” retired Israeli Air Force Brig. Gen. Ephraim Segoli told CNN’s Ian Lee.

Israel is receiving the US Air Force’s variant of the jet, though it has opted to make its own modifications.

The jet comes after the countries recently signed a 10-year security assistance memorandum that will provide $38 billion in aid to Israel.

US military assistance to Israel dwarfs that of any other recipient, with the US providing some $24 billion to Israel during the last eight years, according to National Security Adviser Susan Rice.

Despite this, Republicans have slammed President Barack Obama and his administration for being insufficiently supportive of Israel on policy matters.

“He may be the worst thing to ever happen to Israel, believe me,” Trump said of Obama during his March speech to American Israel Public Affairs Committee.

Netanyahu told “60 Minutes” in an interview that aired Sunday that he is planning on meeting with Trump soon to discuss ending one of Obama’s key diplomatic initiatives, the Iran nuclear pact, which Trump has called “stupid” and a “disgrace.”