A spokesman for the parents of Harry Dunn, the 19-year-old British teenager allegedly killed by an American diplomat's wife in a wrong-way crash, has accused U.S. State Department lawyers of being “cowards” with their “heads in the sand,” according to a report Tuesday.

Spokesman Radd Seiger charged the lawyers with rejecting his request for a meeting with Charlotte Charles and Tim Dunn, Sky News reported.

"Not only has the State Department turned down a perfectly lawful request for a meeting, they're not even abiding by the terms of the extradition treaty,” Seiger told the news outlet.

JOHNSON SAYS CHANCES OF US DIPLOMAT'S WIFE WANTED IN TEEN'S DEATH TO BE EXTRADITED TO UK ARE 'VERY LOW'

"They're cowards and they have their heads in the sand,” he added.

Harry Dunn was killed last year after his motorcycle collided with a car near RAF Croughton, a British military base west of Milton Keynes that's home to a signals intelligence station operated by the U.S. Air Force.

The U.S. State Department has refused to extradite Anne Sacoolas, the wife of a U.S. diplomat, who has been accused of striking the young man as she was driving on the wrong side of the road.

Sacoolas has claimed diplomatic immunity and left the U.K. soon after the fatal crash.

STATE DEPARTMENT REFUSES TO EXTRADITE AMERICAN CHARGED IN DEADLY UK CRASH

"If there's some sort of legitimate national security reason why they can't extradite this lady, then they should make that clear and maybe this family would go away," Seiger told Sky News.

"But they need to look the family in the eye and tell them why they're behaving so completely lawlessly."

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The State Department did not immediately respond to a request for comment from Fox News.