A cockpit recording of dialogue between the two pilots of the Air India flight that crashed last month indicates the captain turned off the switches that controlled fuel flowing to the plane's engines, the Wall Street Journal (WSJ) reported on Wednesday.

The first officer, who was flying the Boeing 787 Dreamliner, asked the more experienced captain why he moved the switches to the "cutoff" position after it climbed off the runway, the report said, citing people familiar with U.S. officials' early assessment of evidence uncovered in the investigation.

The first officer expressed surprise and then panicked, while the captain seemed to remain calm, the WSJ reported.

India's Directorate General of Civil Aviation (DGCA), Boeing and Air India have not commented so far.

The two pilots involved were Captain Sumeet Sabharwal and First Officer Clive Kunder, who had total flying experience of 15,638 hours and 3,403 hours, respectively.

A preliminary report released last week by India's Aircraft Accident Investigation Bureau depicted confusion in the cockpit shortly before the June 12 crash, and raised fresh questions over the position of the critical engine fuel cutoff switches.

It has led to speculation about whether the fuel cutoff was intentional or accidental, prompting strong objections from pilot associations.

The Airline Pilots Association of India has argued the preliminary report showed bias toward pilot error, saying it "categorically rejects this presumption and insists on a fair, fact-based inquiry." The association also asked for an observer status for the investigation to ensure transparency.

The Indian Commercial Pilots' Association warned against making hasty conclusions, stating that the crew acted according to their training and responsibilities under challenging conditions. 

The association urged against vilifying the pilots based on speculation, emphasizing that any speculation "is unacceptable and must be condemned" until the official investigation is completed and the final report published.

Read more: India's aviation minister says no conclusions of plane crash to be drawn until final report

(With input from Reuters)