The objection lodged with An Bord Pleanala by the National Roads Authority (NRA) to the development . . .outlined in this newspaper last weekend . . . leaves absolutely no room for argument.

The agency responsible for our national road network could hardly have been more blunt. Not only did it say that the proposed Ikea store in Ballymun would likely result in "significant delays and congestion" on the M50, but it added that it would "significantly undermine and negate the benefits" of the 1bn upgrade that began recently.

The delays and congestion caused by the development would be "unacceptable on this section of the motorway, which forms part of the most critical artery for traffic distribution around Dublin and which serves as a vital link to Dublin airport and Dublin Port, " the NRA said. It was clear from the additional information provided by Ikea that the Ballymun Road junction of the M50 . . . even after it is upgraded . . . "will be unable to cater for the predicted future traffic levels, " it added, before going on to note that the applicant has "not sought to address these deficiencies or to provide solutions to these issues." Nor, the NRA added pointedly, had these deficiencies been addressed in conditions attached to the planning permission granted by Fingal County Council.

That simply has to be that. Game over.

The alternative is to argue that we should spend 1bn . . . a lot of money, even in these profligate times . . . improving the M50 and at the same time give the all-clear to a development that would likely significantly undermine and negate the benefits offered by that 1bn upgrade.

That has to be a no-brainer for An Bord Pleanala, which will have to make the final decision on the Ikea development in the coming months. In October, the board's chairman, John O'Connor, was explicit in his opposition to building major commercial schemes alongside motorways. O'Connor said that anyone driving around the country could see what was happening with the construction of hotels, business parks and retail warehousing at motorway interchanges. Such schemes were "piggybacking" on new roads with local traffic "weaving on and off over short distances" to get access and running into conflict with long-distance traffic. This affected the capacity of roads and raised safety concerns, he said.

O'Connor specifically cited the M50 as an "extreme example" of piggy-backing commercial developments and said such schemes would face a "high hurdle" in winning board approval. He added that the board would be taking heed of the NRA's arguments against this type of development. Most revealing of all though was his comment that the huge multi-billion euro investment in roads would have to be written off in 10 years unless local authorities stopped granting permission for such schemes. O'Connor deserves praise for his tough-talking, but the Ikea decision will be the acid test of whether An Bord Pleanala is willing to practise what it preaches.

It won't be an easy decision for the board. We know the government is gungho about the Ikea project . . . so much so that it was willing to sacrifice its own carefully drawn-up planning guidelines to accommodate it. The folly of that decision only became truly apparent when, a few months after the government dumped its guidelines restricting the size of retail warehouses, Ikea announced that, in Britain it was planning to build smaller, city-centre shops, a quarter of the size of the company's usual outlets. It did this after the British government refused to give Ikea permission to build a 45m shop near Manchester, arguing that it contravened the government's policy on out-oftown shopping. The Swedish company appealed that decision to the High Court but lost the case, prompting it to announce the major change in strategy.

One can only wonder what would have happened if the government here had similarly stuck to its principles. Does anybody really believe that . . . if the government had stood by its planning guidelines . . . a company as successful and smart as Ikea would have refused to come to the fastest growing economy, and one of the wealthiest countries, in Europe?

But that is now history. The future is of much more concern. Last Wednesday week, the M50 was the scene of a 15-mile tailback that has been described as Ireland's worst-ever traffic jam. If we want to ensure that such traffic jams do not become much more commonplace, we have to start taking planning seriously.

Tough decisions can no longer be shirked and there must be restrictions on urban sprawl, ribbon development and out-oftown shopping centres utilising our new road network. Ikea is a highly reputable company and would be a welcome addition to the retail sector here. But not on the M50, the country's most important, and already extremely congested, road.

There are those in government who . . . no doubt genuinely . . . see Ikea as a key driving force behind the highly laudable Ballymun regeneration plan. But pushing through a development which, in the words of the NRA, cannot be accommodated by the road network and junctions and will likely cause "significant delays and congestion, " is not doing any favours to the people of Ballymun or of the greater Dublin area. It's over to An Bord Pleanala now . . . your country needs you.