IFA has opened disciplinary proceedings against Dele Alli over his gesture during England's World Cup qualifier against Slovakia.
Alli gestured with his middle finger during the 2-1 victory at Wembley on Monday, an act he claims was directed towards team-mate and friend Kyle Walker.
"We can confirm that disciplinary proceedings have been opened following this incident. Please understand we cannot comment further at this stage," a FIFA spokesperson said.
Following Monday night's match it was initially suggested Alli had directed the gesture towards referee Clement Turpin after a coming together with former Liverpool defender Martin Skrtel on the edge of the Slovakia penalty area towards the end of the game that was not given as a foul.
Both the player and England manager Gareth Southgate, though, have since claimed it was in fact aimed in jest at Walker, a former team-mate of Alli at Spurs before his summer move to Manchester City.
Following the game, Southgate was asked about the incident - which came with 13 minutes remaining - and said it was ''mucking about'' with close friend Walker.
Alli also later took to Twitter to explain, writing: ''Just to clarify, the gesture tonight was a joke between me and my good friend Kyle Walker! Apologies for any offence caused! Great win 2nite.''
England goalkeeper Joe Hart offered support for Alli after the 21-year-old Tottenham midfielder came under fire on social media following the broadcast of his actions, while striker Jamie Vardy subsequently brushed off the incident as ''harmless banter'' and said it had been ''blown out of proportion''.
Press Association Sport understands the Football Association have more television coverage of the incident, yet to be broadcast, which could be presented to back-up Alli's stance should it be formally required by the world governing body, who will also have taken into account the view of the referee in his official match report.
Despite the explanations and back-up from both his England team-mates and the FA, Alli is still nevertheless now facing disciplinary action from FIFA, with the sanction of a suspension a possibility as well as a fine.
England won 2-1 at Wembley to move closer to securing their place at next summer's World Cup finals in Russia with goals from Eric Dier and Marcus Rashford having turned the game around after Southgate's men fell behind inside three minutes.
The Three Lions return to action at home against Slovenia on October 5 and need only two points from their remaining two Group F qualifiers to secure a place at the 2018 World Cup.
FIFA's disciplinary process regarding the incident involving Alli would be expected to have been completed one way or another before next month's match at Wembley, which the Spurs midfielder could yet be forced to miss if any ban is indeed handed out.