A panel of scientific experts that advises the Food and Drug Administration on vaccine policy — and that has been the target of criticism from Health Secretary Robert F. Kennedy Jr. — learned on Wednesday that its upcoming meeting to discuss next year’s flu vaccines had been canceled.

The F.D.A. sent an email to members of the panel, the Vaccines and Related Biological Products Advisory Committee, on Monday afternoon informing them of the cancellation, according to a senior official familiar with the decision. There was no reason given. The panel was to meet on March 13.

One committee member, Dr. Paul Offit of the Children’s Hospital of Philadelphia, an outspoken critic of Mr. Kennedy, confirmed the cancellation and warned that it could interfere with or delay production of flu vaccines.

“It’s a six-month production cycle,” Dr. Offit said. “So one can only assume that we’re not picking flu strains this year.”