Moody’s Investors Service said today that it was reviewing the effect of Wachovia’s decision to freeze the short-term accounts of nearly 1,000 colleges who invest through the Commonfund.

The assessment, which will initially focus on 20 institutions that use the money as collateral for debt, could affect some colleges’ credit ratings.

Roger Goodman, a Moody’s vice president, said the ratings agency expected to provide more information about the review in the next day or two.

The freeze, announced on Monday, stems from the pending purchase of Wachovia by Citigroup. The move has left 900 institutions unable to get access to billions of dollars they depend on for salaries, campus construction, and debt payments.

A spokeswoman for Wachovia said today that the bank had restricted withdrawals to ensure an orderly liquidation of the fund, which is dissolving on December 31. Without the freeze, some colleges might have withdrawn all of their money at once, leaving the bank without enough cash to cover the remaining investors.

“This was done to protect our investors,” said the spokeswoman, Laura Fay. “We wanted to ensure that every investor in the fund had fair and equitable treatment should they need to withdraw.” —Kelly Field