Prime Minister David Cameron's promise of an in/out referendum on Britain's membership of the European Union has been backed by Gloucestershire's Tory MPs.
But the county's Lib Dem MP has warned pledging a public vote so far in advance on a yet-to-be-decided deal threatened investment and jobs.
Meanwhile Labour has accused Mr Cameron of "running scared" of the UK Independence Party (Ukip) and his own backbenchers.
In a high-profile speech in London, the PM said the Conservative manifesto for the 2015 general election will ask for a mandate to negotiate a "new settlement" for Britain in Europe, which will be put to voters in a referendum by the end of 2017.
And he said that he would campaign "with all my heart and soul" for Britain to stay within a reformed EU.
At Prime Minister's Questions in the House of Commons, Labour leader Ed Miliband said that his party "do not want an in/out referendum".
And he demanded to know whether Mr Cameron would vote Yes in a referendum if he failed to achieve his negotiating goals.
Speaking after Mr Cameron's speech, Conservative MP for Gloucester Richard Graham said: "This is the right way forward - the PM shares Gloucester's frustrations with the cost of the EU, recognises the importance of the single market and our business with Europe and gives everyone the chance to have their say. And only the Conservatives can deliver that certainty of a referendum."
Hailing it as the most important speech made in recent decades, fellow Tory MP for Tewkesbury Laurence Robertson said: "For the first time since 1975, the British people are going to be given the opportunity to decide their destiny in an in-out referendum.
"This is what I and many others have been fighting for and campaigning in favour of for a very long time. The EU has changed beyond recognition from the EEC which people voted in favour of almost forty years ago, and it's right that people should be asked if they wish to remain members of it or not.
"Of course, all this depends on the Conservative Party winning an outright victory at the next General Election, because Labour and the LibDems are opposed to holding a referendum and are in favour of going deeper into Europe."
Initially striking a conciliatory tone Lib Dem MP for Cheltenham Martin Horwood said: "I think there was a lot in the speech Liberal Democrats wouldn't disagree with. We would say yes to a more flexible and competitive Europe.
"He made quite a strong case for Britain staying in the European Union."
But on the referendum the MP added: "By hyping it up so many years in advance it will pose an immediate risk to jobs and foreign investment in this country. It's going to be exploited by the eurosceptics.
"I think a referendum when we know what it's about is not a bad idea at all. We don't know what that deal is."
Mark Harper, Tory MP for Forest of Dean and Immigration Minister, said: "I support the Prime Minister's announcements today on the European Union.
"The current 'one-size-fits-all' approach taken in Brussels is not sustainable. The British public quite rightly feel that the EU has moved in a direction that we never wanted - we signed up to a Common Market, not a United States of Europe.
"The Prime Minister is right that we should reform the EU and our relationship with it and then campaign to stay in that reformed EU - that's in our national interest. We trust the British people to make the final decision."
Tory MP for the Cotswolds Geoffrey Clifton-Brown said: "It think it's a really positive way of taking this whole difficult European issue forward.
"I can see it from my constituency correspondence there's a lot of concern over Europe.
"He's given a real, impetus to our partners to try and negotiate something positive.
"I am one of those that wants to see an improved relationship with Europe."
Tory MP for Stroud Neil Carmichael hailed the 'powerful' speech by the PM.
What did you think of the PM's speech? Should we stay in Europe under renegotiated terms or get out now? Let us know what you think below.