Minister for Finance Brian Cowen defended the Government's decision that civil servants seeking promotion must make a commitment to move outside Dublin if necessary.
Mr Cowen said that "where a promotion arises for a post which is being decentralised as part of the decentralisation programme, it is entirely reasonable for the employing Department to ask staff accepting that promotion to agree to move with the post".
He added that the Government had made clear on a number of occasions that participation in the programme was voluntary and nobody was being forced to decentralise.
"Discussions are continuing between management and the civil service unions with the aim of agreeing new promotion and recruitment mechanisms to support implementation of the programme," Mr Cowen said.
"It would not be appropriate for me to comment in detail on these discussions."
He said the Government wanted to reach a reasonable agreement on those issues with staff unions: an agreement which supported the early and efficient implementation of the programme, while taking account of the legitimate desires of staff remaining in Dublin to maintain appropriate opportunities for promotion.
Fine Gael finance spokesman Richard Bruton said there were about 17 locations in the first decentralisation phase published by the Minister, with a tiny proportion of Dublin-based employees having opted to move.
"With regard to the four State agencies, only 2 per cent, 4 per cent and 8 per cent have applied," he added. "Less than a quarter of public servants based in Dublin are opting for positions."
Mr Bruton asked if Mr Cowen was telling those based in Dublin that their opportunities for promotion were now entirely closed off because of the selection made.
"How does that tally with the concept of a voluntary programme?" he asked. "People can exercise their right not to move, but their career path will grind to a halt if they do so."
Mr Cowen said the Government recognised the concerns of those affected by decentralisation. He added that imposed solutions, by their nature, were measures of last resort and were rarely as effective as agreements reached on the basis of goodwill and compromise.