US comedian and actor Bill Cosby's record of big donations to colleges and other institutions has been a key part of his rosy public image - but the rising tide of allegations made by women accusing him of sexual assault is threatening to overshadow his generosity.

North Carolina's High Point University has removed the 77-year-old entertainer from its National Board of Advisers, a panel that includes retired US General Colin Powell.

The university referred to Cosby as "one of the most influential performers of our time" when it announced his appointment last July.

Berklee College of Music said it was "no longer awarding" an online scholarship in Mr Cosby's name.

No institutions have publicly renounced any of the tens of millions of dollars Cosby and his wife Camille have given over the years, or rejected new donations.

Michael Chatman, a philanthropy expert, said: "Nothing has been proven and he has not been charged."

Cosby's lawyer Martin Singer, has called the growing number of allegations "unsubstantiated."