Environment Minister John Gormley had publicly expressed a belief the law would be passed in time to hold elections for the position in the autumn.
However, in recent weeks, the production of legislation was delayed and, at yesterday’s meeting, the Cabinet decided to postpone discussion on it until September.
A Government spokesman for the Green Party said Mr Gormley had hoped the law would be quicker to deliver.
In June, Mr Gormley said the Dáil would sit later in July if it had to in order to get the bill passed, but he also accepted it was a complex piece of legislation and that it would be difficult to meet the target he had set.
The hold-up is being linked to the White Paper on the reform of local government, which will come before the Government in the autumn. Because both items were connected it was decided to delay the mayoralty discussion.
The spokesman said the Programme for Government had originally envisaged an election in 2011 and this was still achievable.
He denied it in any way indicated a reluctance on the Government to trigger a mayoral election in Dublin because this would fuel demands for the three outstanding by-elections, in Dublin South, Waterford and Donegal South West, to be called. A Government spokesman said there has never been any discussion at Cabinet level on the holding of the by-elections.
The Cabinet met for the last time until September 1.