SEOUL (Reuters) - South Korea's transport ministry is investigating reports that the daughter of the chairman of Korean Air Lines Co, who oversees in-flight service, caused a plane being pushed back from a gate to return in order to expel a flight attendant.

Heather Cho, 40, was in a first class seat on a flight bound from New York's John F. Kennedy International Airport for Incheon, near Seoul, on Friday when she took issue with a flight attendant who handed her macadamia nuts in a bag and not on a dish, according to local media reports and an industry source.

Cho, a vice president at the airline, summoned the cabin crew chief to ask whether the flight attendant was following the in-flight service manual, said the industry official, who was briefed on the matter but declined to be identified due to the sensitivity of the matter.

When the crew chief could not answer the question promptly, Cho ordered the crew chief to disembark, prompting the pilot to return the plane to the gate, the industry official said, confirming media reports.

Korean Air confirmed on Monday that the executive involved in the matter was Cho, and said she would not be available for media comment.

It said the flight arrived at Incheon 11 minutes behind schedule and the decision to expel the crew chief had been made in consultation with the pilot.

It did not say why the crew chief was ordered off the plane.

South Korea's transport ministry said on Monday that it was investigating the case involving a vice president of the airline and would take appropriate measures if any laws or industry regulations had been broken.

Heather Cho is the oldest of Korean Air Chairman and CEO Cho Yang-ho's three children, all of whom are executives at the airline.

(Reporting by Joyce Lee and Kahyun Yang; Writing by Jack Kim; Editing by Tony Munroe and Ryan Woo)