The state-owned carrier said in a statement that the breach of Indian civil aviation requirements has "serious implications on passenger safety". Air India said it wanted to assure its passengers that "under no circumstances" would their safety be compromised.
Earlier, an airline official said that Kathpalia was asked to resign by India's civil aviation ministry. But in its later statement Air India said he had been relieved of his duties "with immediate effect".
The official said Kathpalia has also stepped down from the company's board.
Kathpalia, who said on Sunday he had not been drinking and was the victim of internal feuding, could not be immediately reached for comment on Tuesday.
Amitabh Singh, executive director for training, will take on the operations director's responsibilities. The investigation into Kathpalia's behavior will be conducted by the airline's chief vigilance officer, Air India said.
India's air safety watchdog had already suspended Kathpalia's license for three years after he failed the breathalyser tests.
This is the second time Kathpalia has been in trouble over alcohol tests. He was suspended for three months in 2017 for allegedly refusing to take breathalyser tests.
(Reporting by Aditi Shah and Neha Dasgupta Editing by Martin Howell and Louise Heavens)
(This story has not been edited by Devdiscourse staff and is auto-generated from a syndicated feed.)