NEW YORK (CNN/Money) - Arthur Andersen LLP, which earlier this week called off a global merger with KPMG International, tentatively agreed Thursday to sell part of its tax practice to its U.S. rival Deloitte & Touche.

Andersen said it signed a memorandum of understanding for a significant number of its U.S. tax partners and tax professionals to join Deloitte. Details will be refined during a review period but the deal is expected to close as early as April 30, Andersen said.

Terms of the transaction were not announced. However, the deal could involve as many as 500-to-600 tax partners moving to Deloitte, a source familiar with the situation told CNNfn.

"While our firm will retain appropriate tax expertise in a manner consistent with these reforms, Deloitte will provide a significant number of our people with continuing career opportunities and our clients with continued quality service from recognized and respected professionals," Andersen Managing Partner Larry Gorrell said.

The embattled accounting firm, which is currently fighting a federal indictment for allegedly obstructing justice when it shredded Enron Corp. documents, said the sale is part of reforms called for by former Federal Reserve Chairman Paul Volcker. Volcker chairs an independent board charged with implementing change at Andersen.

Last week, Andersen introduced a new transition team that will lead it back to becoming a pure audit firm, as part of the changes called for by Volcker. The former Fed chairman has also recommended that Andersen split off its consulting practice and install a seven-member independent board to take control of Andersen. Volcker would also head that board.

Earlier this week, Andersen called off global merger talks with KPMG International. The proposed deal would have combined the non-U.S. businesses of both firms. Andersen has failed previously to merge or sell all or part of its businesses to rivals Ernst & Young and Deloitte.

The troubled accounting firm is also weighing a possible settlement with the Justice Department. Andersen has lost more than 100 audit clients and more than half came after the March 14 indictment, said Art Bowman, editor of Bowman's Accounting Report.

Andersen said Thursday it would not plead guilty in a courtroom but would consider making a public admission of responsibility for shredding Enron documents.