WASHINGTON (Reuters) - Boeing Co BA.N has received a $3.9 billion contract to build two 747-8 aircraft for use as Air Force One by the U.S. president, due to be delivered by December 2024 and painted red, white and blue, officials said on Tuesday.

The Pentagon announced the decision on Tuesday, saying Seattle-based Boeing’s previously awarded contract for development work had been expanded to include design, modification and fielding of two mission-ready presidential 747-8 aircraft.

The contract followed the outlines of the informal deal reached between Boeing and the White House in February. That agreement came after President Donald Trump objected to the $4 billion price tag of a previous Air Force One deal, complaining in a Twitter post that “costs are out of control” and adding “Cancel order!”

The White House said in February the new deal would save taxpayers more than $1.4 billion, but those savings could not be independently confirmed.

Air Force budget documents released in February for fiscal year 2019 disclosed a $3.9 billion cost for the two-aircraft program. The same 2018 budget document, not adjusted for inflation, showed the price at $3.6 billion.

The Boeing 747-8s are designed to be an airborne White House able to fly in worst-case security scenarios, such as nuclear war, and are modified with military avionics, advanced communications and a self-defense system.

A congressional official briefed on Tuesday about the deal indicated it was little changed from the informal agreement reached in February, calling for two 747-8 aircraft to be built for $3.9 billion and delivered by December 2024.

Trump told CBS in an interview that aired on Tuesday that the new model Air Force One would be updated on the inside and have a different exterior color scheme from the current white and two shades of blue dating back to President John F. Kennedy’s administration.

“Red, white and blue,” Trump said. “Air Force One is going to be incredible. It’s going to be the top of the line, the top in the world. And it’s going to be red, white and blue, which I think is appropriate.”