RTÉ will be unable to redevelop its Montrose headquarters unless Dublin City Council agrees to rezone adjoining land owned by the station, which it wants to lease out to help fund the €350m development.

The proposed works at Donnybrook in south Dublin will rely on the future leasing of onsite facilities. Current zoning on the site rules this out.

Now crunch talks on the building of a primary school on the land could be the difference between the station securing zoning or not.

Councillors, concerned with the lack of educational facilities in the area, are adamant that a primary school should be part of any new development on the land.

Speaking to the Sunday Tribune following the council debate on the development plan, councillor Dermot Lacey said: "Councillors have said that one of the big local issues is the lack of places in a local primary school. There isn't a lot of land and one of the possible sites would be on part of the RTÉ grounds.

"We have said that if there is to be a redevelopment of the RTÉ lands there should be a degree of community gain."

A spokesman for RTÉ refused to comment on the "hypothetical" scenario in which a failure to secure zoning would scupper its plans.

"We have no intention at present to sell anything; our desire is to lease facilities to assist any debt that would occur in the build," he said.

Meanwhile, ambitious plans for another underground traffic tunnel in the capital have also been left in the draft development plan despite that fact that it would be covered under strategic infrastructure legislation which bypasses planning permission requirements.

The tunnel, which would cost hundreds of millions of euro to construct, would form part of an eastern bypass route connecting the northern end of Dublin Port to the south side of the city, running under Sandymount, Merrion strand and Booterstown marsh.

It is deemed more palatable to councillors than an alternative road route over Dublin Bay.

Other aspects forming part of the draft development plan – which will now go to public consultation – include objections to the controversial Poolbeg incinerator, the retention of traditional shop fronts and the introduction of measures designed to deal with semi-completed apartment blocks.

Motions calling for the protection of Bewleys as a café, the expansion of the free-bike scheme, building heights, restrictions on outdoor advertising and an 'Irish only' policy for housing estate names have all been included.