"Mr. @StephenConstan has announced his resignation as the Head Coach of the Indian National Team. We haven't received any official communication from him yet but we accept his decision & thank him for his contribution to #Indianfootball: Mr. Kushal Das, General Secretary, AIFF," the tweet said.
His contract was to end on January 31.
India were on the verge of booking its maiden knock-out round berth as the final Group A match was 0-0 till the 90th minute when Bahrain earned a penalty which the West Asian team converted to win the game under dramatic circumstances.
India needed just a draw to qualify for the Round of 16 but the defeat meant that it finished at the bottom of the four-team Group A to crash out of the tournament.
The Anglo-Cypriot coach took over the reigns of the team in 2015 for an initial two-year tenure. He was given one-year contract extension twice.
It was his second stint as India coach after serving as coach in 2002-05.