A new law introduced by Minister for the Environment Alan Kelly to increase ministerial planning powers over local authorities could significantly change how planning operates in Ireland, according to the professional body representing planners in Ireland.

Speaking on RTÉ’s This Week, councillors opposed to the law said that it was a "power grab", and claimed it could significantly limits the planning powers of local government.

The Irish Planning Institute (IPI) voiced concerns about the Planning and Development (Amendment) Act 2015 which became law on 29 December, during a consultation period which began the month beforehand.

The Act gives new powers to environment ministers to issue mandatory orders to local authorities on planning matters which they had previously decided for themselves.

Under the new law, Department of Environment, Community and Local Government planning guidelines, which were previously advisory and to be considered at the discretion of local authorities, can now become mandatory instructions which must be adopted if an environment minister so orders.

While environment ministers have always had the power to overrule councils, in practice the new law will allow wider and much earlier direct involvement in county planning matters and will limit, in practice, the discretionary power of local council planners in such cases.

IPI president Deirdre Fallon said: "The guidelines that were produced by the minister [before the new law] set out broad policy directions and individual planning authorities and councillors had some discretion as to how they would implement them in their own plans. The new revision to the Act removes that discretion."

"The Act was published in draft form as a Bill in November - and at that time we had raised our concerns with the minister in relation to the potential of the Act to reduce the local autonomy of councillors and to change the relationship that exists at the present between councillors, planning authorities and the ministers," she added.

Local authorities are currently considering what the implications of the new law are.

In a letter from the department to all local authorities on 13 January, it said the housing market difficulties are the primary background to the new law and that streamlining planning is hoped to help housing supply.

In the circular, councils were told that the Act "introduces a new power whereby the minister may, within the Section 28 guidelines, expressly state specific planning policy requirements to be applied by planning authorities, or An Bord Pleanála, as appropriate, in the exercise of their planning functions."

"Therefore, the content of guidelines will distinguish between advisory or general commentary, on the one hand, and specific requirements that must be mandatorily applied by planning authorities.

"This amendment is necessary to underpin the new revised guidelines that provide for national minimum apartment standards to be applied by planning authorities," the letter stated.

Mr Kelly told the Dáil on 26 January, after the law came into force, that it "strengthens the status of aspects of planning guidelines issued to local authorities on planning matters to ensure their consistent application, especially relating to apartment standard guidelines."

The Act is intended to "preclude the adoption by local authorities of their own local standards thereby preventing a multiplicity of approaches throughout the country and will require local authorities to comply with the national guidelines issued by the Minister," according to the letter from the Department to local authorities.

However, speaking on RTÉ's This Week, councillors claimed that the law seriously reduces the power of local authorities and will dispense with local expertise and knowledge.

Offaly County Councillor John Leahy and Renua Dáil candidate for Offaly said: "Local authorities are there for a reason and significant powers are being eroded. Involvement of local authorities in planning is critical. They know what services are there, what the needs of a county are. They’re on the ground.

"I think the minister is taking away key responsibilities from local authorities and that it’s a bad move. He’s taking away too from the expertise that local authorities have."

Mr Leahy also criticised the swift passage of the legislation from draft in November to enactment in December, saying that the time of year approaching Christmas, the scheduling of his own council’s meetings and election speculation meant there was not time for adequate debate.

Green Party councillor and Dáil candidate for Dun Laoghaire Ossian Smyth claimed that the plans were a "power grab" to take planning responsibility away from local authorities.

"It turns the planning system away from one where people think about the plans that they want to make for the future to one where the minister just writes something down on a piece of paper and says: 'These are your plans.' It allows the minister to issue an edict - it makes a joke of the whole planning system and it means that the work that’s being done by councillors in forming plans is effectively worthless," added Mr Smyth.