Cardiff council has deferred discussion on a key planning application for a retail development which forms part of Cardiff City's new football stadium.
The new stadium has been on the drawing board since 2000
Councillors will now discuss the plans to allow more shops next month.
Council leader Rodney Berman said the stadium timetable would not be affected by the deferral, which was for "legal and technical reasons".
Meanwhile, the plans have been criticised by some retailers, who fear they could damage the city centre.
On Wednesday, two applications from the retail developers were approved by the council's planning committee.
But the council said that a planning agreement with American store group Costco had not been finalised for "legal and technical reasons".
That application, along with three other applications for the Leckwith development, will now be discussed at the January meeting.
Cardiff City owner said the deferral was "very frustrating".
"But I am pleased to see...that this delay will not affect the development and overall timescale for our new stadium," he said.
He added he was meeting Cllr Berman to discuss the issue on Thursday.
The development in the Leckwith area a mile or so from the showpiece Millennium Stadium will replace the club's existing Ninian Park home.
It will seat about 30,000 fans, with the possibility of an increase to 60,000 in the future.
The sale of shop space will provide some of the money needed for the £100m project, which will also include a hotel and spa.
Building work could start once planning permission is granted.
This is how planners think the new Cardiff stadium would look
Cllr Berman said he wanted to reassure the developers and fans that the council was "strongly committed" to the stadium.
He said: "We appreciate the eagerness of the club, retail developers, the contractors and Cardiff City fans alike to see the stadium completed.
"But I would stress that this deferral will not materially affect the overall timescale.
"I am optimistic that we are on track to complete the complex and necessary agreements early in the New Year."
The expansion at Leckwith is being planned at the same time as another major development, including the John Lewis department store, is being planned for the city centre.
But David Hughes-Lewis, chair of the Cardiff Retail Partnership, said more out-of-town development was not needed in Cardiff.
"They were given planning permission originally against a lot of objections from retailers in the city - but more importantly from retailers from the areas of Canton and Leckwith," he said.
"Despite that they got their planning permission and now they are looking for more. It's going to jeopardise the city centre."
Mr Hughes-Lewis said the new St David's 2 shopping development in the city centre was "going to double the size of the retail area in the city centre. More out of town developments are not needed, not in Cardiff".