Republic expects UK to do a deal with the EU
The Irish Government's UK ambassador has said he is confident a deal will be done between Britain and the EU over Europe.
Proposals recently put forward in an effort to avoid a Brexit are "significant", Dan Mulhall added.
He said Ireland supports British efforts to improve competitiveness - promoting the single market; boosting the digital economy and tackling climate change.
He said: "I am confident, I am optimistic that a solution will be found that will enable the government to go to a referendum with a new set of proposals for the British public."
A summit of EU leaders on a Brexit is due next week.
Prime Minister David Cameron has been meeting key European Union figures over a draft deal put forward by European Council president Donald Tusk aimed at keeping Britain in.
Mr Cameron has called for greater British sovereignty and restrictions on in-work benefits for EU migrants known as an "emergency brake".
The Northern Ireland Affairs Committee of MPs has been holding an inquiry in to the effect of a Brexit on Northern Ireland.
Mr Mulhall told the committee the Irish Government supported Britain on welfare fraud reform but said the provisions were still being worked on.
He said Ireland had a similar proportion of its population born outside the state as Britain but there was not the same focus on resistance to migration or free movement.
The ambassador said the renegotiations reminded him of Ireland's experience after voters rejected the first referendum on the Lisbon Treaty, which reformed the EU, and the Republic had to seek further concessions.