Austin was provisionally barred by CONCACAF last week having been in charge of the organisation for just four days following the suspension of the body's long-standing president Jack Warner, who is facing corruption allegations.
While Warner was suspended by FIFA after allegations of bribery and pending further investigations by its ethics committee, no such charges have been made against Austin.
CONCACAF has declined to explain the detailed reason for Austin's removal, official documents referring only to an "apparent infringement" of statutes.
"We can confirm that FIFA has today notified CONCACAF that the FIFA disciplinary committee has extended the provisional suspension of Lisle Austin at a worldwide level," FIFA said in an email to Reuters.
The suspension of Austin was announced by "the majority of the (CONCACAF) executive committee" and signed by four members including U.S Soccer president Sunil Gulati and Mexican football chief Justino Compean.
In the short time before he was suspended, Austin tried to fire CONCACAF's general secretary Chuck Blazer and announced he was conducting a 'forensic audit' of the body's accounts over the past five years.
Austin also said that he had tried to revoke Blazer's signing authority over the bank accounts of CONCACAF.
Blazer declined to discuss the reasons for Austin's suspension when asked at a news conference in Dallas on Sunday but had previously rejected Austin's right to fire him.
Austin's spokesman, Ryan Toohey, said the official yet to be informed by FIFA of the decision.
"Mr Austin has not been notified of any action by FIFA regarding any suspension. There is no existing suspension so there is nothing to extend," he told Reuters.
"Lisle Austin remains acting president of CONCACAF and has urged FIFA to intervene and resolve these so-called leadership questions," Toohey said.
"These actions and additional statements questioning my leadership are being engineered by a faction of CONCACAF attempting to unlawfully seize control," he said.
"The actions and statements of these persons are beyond their authority and are neither the actions of, nor binding upon, CONCACAF. As acting president I will take all appropriate steps to remedy these actions," said Austin.
"The organization is under attack from within by those who refuse to respect the statutes of CONCACAF and have no regard for the rights and interests of the members at large.
"I will not stand idly by while this happens and hope, through FIFA intervention or other means, to restore order to CONCACAF as soon as possible."
