A plea deal in the Wendy Machanik fraud case was not concluded as expected on Monday because a tax matter arose during negotiations, the Specialised Commercial Crimes Court in Johannesburg heard.

"These have proceeded to a near finality. There is only one further aspect that has to be clarified," prosecutor Adele Carstens said.

These related to the SA Revenue Services and a docket had been opened, she said. The case was therefore postponed to July 31.

The possible plea agreement is in terms of section 105(a) of the Criminal Procedure Act, which permits a guilty plea in exchange for information.

Bail for Machanik and her co-accused Bruce Bernstein was extended. The two were arrested last year on charges of conspiracy to commit fraud, failure to keep accounting records and failure to reflect over 100 transfers between the company's trust and business accounts. The amount involved is around R28 million.

If by that date negotiations have not been finalised Carstens would insist on a trial date.