WASHINGTON — A meeting with lawmakers vanished from the White House schedule. A ceremonial executive order signing was abruptly canceled. A statement about how a signature campaign promise will be paid for was walked back.

The first days of any new president's term are disorderly, as a sprawling government bureaucracy and overwhelming global responsibilities are suddenly thrust upon an administration that is trying to hit the ground running and sometimes just to get the phones working.

By any measure, Thursday was a chaotic day in President Donald Trump's White House.

The confusion began early, when the president left the White House nearly an hour late for his first trip away from Washington, a quick jaunt to Philadelphia to speak to a Republican congressional retreat.

While airborne, White House aides confirmed that a meeting between Trump and Utah Sen. Orrin Hatch and Texas Rep. Kevin Brady that was scheduled for the president's return had been postponed until next week — and that Hatch, unbeknownst to the press, had actually met with Trump the night before.

On the return flight to Washington, White House press secretary Sean Spicer announced to reporters on the plane that the administration was working with Congress to impose a 20 percent tax on Mexican imports to pay for the southern border wall that Trump had made the centerpiece of his campaign.

"By doing that, we can do $10 billion a year and easily pay for the wall just through that mechanism alone," Spicer said. "This is something that we've been in close contact with both houses in moving forward and creating a plan."

The surprise announcement, meant to fulfill Trump's declaration that Mexico would pay for the wall, led to breaking news alerts lighting up phones across Washington.

But less than an hour later, reporters in the White House press room were hurriedly escorted to Spicer's office. He walked back his earlier comments, explaining that the tax on Mexican imports "was just one option" and that no final decision had been made.

Spicer also announced that an executive order signing — traditionally a staid, painstakingly planned affair, complete with briefing papers and detailed memos — that was scheduled for the Oval Office just minutes later was being postponed because Trump had arrived back at the White House too late in the day.

Spicer said the administration was still sorting out the "sequencing" of upcoming orders and that Trump was still making suggestions.

"As you probably can tell, he's very hands-on when it comes to these executive orders," the press secretary said.

And the order itself, which would commission an investigation into unsubstantiated claims of widespread voter fraud, stemmed not from a campaign promise, but rather Trump's public musings on the subject in recent days.

An environment of chaos is not new for Trump, who at times seems to thrive on disorder.

He sowed chaos in the campaign, pitting factions of his aides against each other, and he frequently changed his mind on issues based on his most recent conversations. His aides often woke up surprised to Trump's early morning, out-of-nowhere pronouncements via Twitter. The candidate himself frequently made outlandish proclamations — like his insistence that President Barack Obama was the literal "founder" of the Islamic State group or his invitation for Russia to hack Hillary Clinton's emails — only to moderate them in the following days.

But the Trump administration is far from the first to experience some early growing pains.

It took more than a day for staffers in President George W. Bush's press office to be able to get all their phones and computers to work in 2001.

And the very first moments of Obama's term in 2009 were muddled when Chief Justice John Roberts bungled the oath of office, forcing a do-over the next day at the White House. Staffers had to rely on reporters to guide them to the Diplomatic Room for the ceremony.

Reach Lemire on Twitter at http://twitter.com/@JonLemire