To add details, comments, and correct a grammatical error in the first paragraph

WASHINGTON, July 20 (Reuters) - Experts said the decision to ground the U.S. presidential plane (Air Force One), a gift from Qatar to U.S. President Donald Trump, was likely related to security upgrades, but they raised questions about whether one month would be enough to significantly enhance the aircraft's defenses.

Trump said on Sunday that the Boeing 747, which he first flew on July 1, would be upgraded and equipped with the latest capabilities and equipment, a process he said would take about a month.

The plane's security readiness came under renewed scrutiny after Trump abruptly resorted to an older presidential aircraft for his trip from Turkey to Britain on July 8, at a time of heightened tensions with Iran.

The new aircraft, whose colors Trump chose to be red, white, dark blue and gold, is a Boeing 747 model that Qatar gifted to the United States last year, and which was upgraded by the defense contractor L3 Harris Technologies.

This aircraft is intended to be a temporary replacement, given that Boeing is facing difficulties in delivering next-generation presidential aircraft.

Douglas Burke, executive director of the Mitchell Institute for Aerospace Studies, said, "The standard U.S. presidential fleet (Air Force One) has a sophisticated suite of protection systems, including anti-missile systems, but it appears the White House agreed to back the Qatari aircraft with a lower level of protection in order to speed up its flight."

Berkeley added that the aircraft was likely designed to operate in "neutral or low-level" threat conditions, and that officials are currently working to add other defensive measures.

He went on to say that completing any work within a month would apparently be limited to non-kinetic systems, such as electronic jamming devices, infrared "blinding" devices designed to mislead heat-seeking missiles, and possibly foils, which are a cloud of thin metal strips launched from an aircraft to scatter radar signals and neutralize radar-guided munitions.

He noted that infrared-guided missiles have become an increasing concern for military planners, given the difficulty of detecting them compared to traditional radar-guided threats, and their "potential to appear suddenly."

The U.S. Air Force declined to comment. White House spokeswoman Caroline Leavitt said today, "The new presidential aircraft is perfectly safe for the president's travel, but it will undergo further upgrades and enhancements this fall, which will take about a month to complete. During this time, the president will travel on the older presidential aircraft."

“There’s not much they can do in a month,” said Mark Cancian, a senior adviser at the Center for Strategic and International Studies. He agreed that the work would likely be limited to software updates or additions such as heat flares or decoy foil.

He added that the decision to change the plane in Türkiye likely came after updated intelligence about threats from Iran, which led officials to conclude that the level of threat exceeded what the Qatari plane could handle.

Democrats questioned the speed at which the aircraft was put into service, arguing that more time was needed to complete the security upgrades.

Senator Jeanne Shaheen said at the Farnborough Airshow that Congress needed to examine the aircraft's safety. She added, "We knew there were some issues with the aircraft's safety. We knew that from the beginning."