The School Food Trust said hot tea and coffee have "minimal" nutritional benefits and pose a risk.
The Trust -- part of the government drive to improve the food quality in schools -- said it did not want to ban them but will hold a consultation on voluntary restriction code.
However, Mick Brookes, of the National Association of Head Teachers, said, "This nannying has to end."
In addition, UKIP MEP Godfrey Bloom called the idea "utterly stupid," adding, "Their pettiness knows no bounds."
Children's Minister Kevin Brennan backed the traditional brew, saying, "Nutritional standards specifically allow tea and coffee. There is no intention of banning them."
In a separate statement, the Trust called the issue "a storm in a tea cup," adding, "The British cuppa is an institution."
From the February 18, 2008, Prepared Foods e-Flash