Following the meeting in Rabat, attended by Infantino, secretary general Mattias Grafstrom and members of FIFA's management board, FIFA said its leadership had reaffirmed its full support for the president while acknowledging that the handling of the withdrawn FIFA Forward Enterprise proposal should have been different.
In a statement, FIFA said a separate letter had been sent to FIFA Council members and the 211 member associations apologising for the errors and promising a review.
It added that, with the proposal withdrawn, FIFA would "no longer tolerate any attacks on its integrity, good governance and due process" and would take all necessary measures to protect its reputation.
Vehicles believed to be carrying Infantino and Grafstrom were seen leaving FIFA's Africa office in Sale after the meeting, which came amid mounting criticism of Infantino's leadership ahead of next year's presidential election.
The meeting followed last week's withdrawal of a proposal to sell a 20% stake in a new commercial rights entity to private investors in a deal that would have raised about $4.2 billion for football development.
The proposal, which also drew scrutiny because of the involvement of a company with family links to U.S. President Donald Trump, prompted fierce criticism from European soccer's governing body UEFA and other stakeholders, who accused FIFA of poor governance and a lack of consultation.
The apology underscored FIFA's acknowledgement that mistakes had been made in the handling of his proposal for a new commercial rights body, which has become the most serious challenge to his leadership since he became FIFA president in 2016 after triggering a torrent of criticism from UEFA, several member associations and senior FIFA officials over governance and consultation.
His backdown last Friday has done little to assuage those critics, most notably UEFA, which accused him of selling the soul of the game and has said it no longer has confidence in his leadership.
That has cast a shadow over Infantino's re-election for a fourth term at the FIFA Congress in Morocco in March, which had looked like a foregone conclusion two months ago.
A handful of European federations have withdrawn their backing for the Swiss Italian, but perhaps more damaging are the messages coming from Infantino's FIFA colleagues.
Canadian Prime Minister Mark Carney also questioned Infantino's leadership on Wednesday, saying he has lost confidence in the FIFA president after learning senior advisers had not been consulted on the abandoned proposal.
"I don't have confidence in Mr. Infantino," Carney told reporters, adding that failing to inform senior executives and fellow board members of such a significant proposal "should be fatal" for any leader.
Grafstrom had sent an internal memo to staff lamenting the "sad and reproachable series of events" that led to the project being "permanently abandoned", two sources told Reuters.
"Individuals, unstable moments and unfortunate episodes come and go. The institution, its mission and its responsibility towards world football continue," the Swede added in the letter, which made no mention of Infantino by name.
His words echoed those of FIFA's Chief Operating Officer Kevin Lamour, who said last week that staff had been "deceived" over the plan which he described as the project of one person.
Infantino's senior adviser Carlos Cordeiro resigned in protest at the plan last week. Arsene Wenger, FIFA's chief of Global Football Development, said he had not been involved in drafting the proposal, and called the decision to withdraw it "absolutely necessary".
Former Portugal great Luis Figo, who had planned to run for the FIFA presidency in 2015, said Infantino should resign over the affair, while UEFA Vice-President Laura McAllister told Reuters the controversy surrounding the abandoned proposal had brought the FIFA president's leadership to a crisis point.
Survive until election
Infantino has spent the past week in Morocco, which will co-host the World Cup in 2030 and whose football association has announced its continued support for him.
The meeting was widely seen as an effort to reinforce support for Infantino and ensure that he emerges from the crisis with enough backing to remain the favourite for re-election in March.
An Extraordinary Congress could be called if 43 or more FIFA member associations make a formal written request for one.
Qatar, which hosted the 2022 World Cup, Kuwait, Lebanon, Sri Lanka, Indonesia and the Philippines have declared their loyalty to Infantino.
Infantino has always enjoyed a lot of support away from the traditional heartlands of the game, where impoverished football associations rely on FIFA's largesse to operate.
But European Leagues, which represents more than 1,300 clubs across Europe, said FIFA must not be allowed to "continue taking unilaterally disruptive decisions" that affect clubs, players and fans. It also criticised the "impractically short assessment timeline" of four weeks given by FIFA to study the plan to expand the World Cup from 48 to 64 teams for the 2030 edition.
African administrators back Infantino
Leading African football administrators have sent messages of support as Infantino looks to the continent's 54 members for backing. The African confederation (CAF) has yet to take a stance.
The executive committee of the smallest and least wealthy regional confederation, Oceania, will meet next Wednesday to discuss their approach.
Under FIFA rules, the vote of San Marino, whose men's team are ranked 211th and last in the world rankings, counts as much as that of World Cup winners like Brazil, Germany, Argentina and Spain.
One clear advantage for Infantino as he looks to extend his presidency until 2031 is that no clear candidate to stand against him in March's election has yet emerged.
Jordan FA President Prince Ali bin Hussein has twice stood for the post, and he made his position clear on Tuesday when he accused FIFA of "blackmail", saying it had offered to help solve problems in exchange for endorsing Infantino.
"We did not endorse him before and certainly will not now," Prince Ali wrote on social media.
A FIFA spokesperson rejected reports that Infantino had made promises over the host of the 2030 World Cup final.
"It is false and misleading to claim the FIFA president has made any promise in relation to hosting the FIFA World Cup 2030 Final. A decision will be made by FIFA in due course," the spokesperson said.