WASHINGTON – The head of Delta Air Lines on Friday joined the growing opposition to the Transportation Security Administration’s new policy allowing passengers to carry small knives onto planes.

Delta CEO Richard Anderson said in a letter to TSA Administrator John Pistole that he shares the “legitimate concerns” of the airline’s flight attendants about the new policy.

Allowing small knives to be carried on board after a ban of more than 11 years “will add little value to the customer security process flow in relation to the additional risk for our cabin staff and customers,” Anderson said in the letter, which was obtained by The Associated Press.

“If the purpose is to increase security checkpoint flow, there are much more effective steps we can take together to streamline the security checkpoints with risk-based screening mechanisms,” he said.

Delta, based in Atlanta, is the world’s second-largest airline. It is the first major airline to join not only flight attendants but pilots, federal air marshals and insurance companies in a burgeoning backlash to the policy. Pistole announced the policy on Tuesday.

TSA spokesman David Castelveter declined comment. He said TSA plans to implement the policy on April 25 as scheduled.