Donald Trump’s big, beautiful new plane from the government of Qatar has arrived – but the US president says it’s too big to be his personal perk.

The problem for the US president is not the smack of impropriety that comes with accepting a luxury 747 jumbo jet from the Gulf state and intended as a replacement Air Force One – Trump has already brushed off any criticism on that front.

Now that it’s arrived in the US, Trump says it’s too big to be his plane. The Qataris have given the president a Boeing 747-8, a stretch model of the jumbo that is more than 18ft longer than the much older 747-200B that flies as the current Air Force One.

“Frankly, it’s much too big,” Trump told reporters during a question-and-answer media session in the Oval Office at the White House on Wednesday afternoon, as he tried to explain why he regarded it as a gift to the nation rather than a perk for him as an individual.

He called the new jet a “beautiful, big, magnificent, free airplane for the United States air force”. Trump continued: “They tried to say: ‘Oh, it’s Trump’s airplane.’ Oh, yeah, sure. It’s too big, frankly, it’s much too big.”

The original offer from Qatar set off a firestorm of criticism of Trump, from both political parties, particularly following his visit to the country earlier this month where he focused most vigorously on trade and business deals. The US senator Cory Booker and other prominent Democrats slammed the arrangement and Chris Murphy, the Connecticut senator, called the gift “the definition of corruption” and “wildly illegal”.

Asked on Wednesday whether the jet is definitely going to become Air Force One, the official plane of the US president, Trump said only that the aircraft was in the US and “being re-fitted for military standard”.

He admitted he doesn’t know how much the re-fitting will cost but guessed “a hell of a lot less than building a new one”. He again criticized Boeing, the troubled US aircraft manufacturer, for delays in replacing the current jet used as Air Force One, which dates back to the early 1990s, apparently necessitating an expedited replacement from another country.