William Hague has warned Tory Eurosceptics hoping to get powers back from the EU that the opportunity for doing so could be "many years" away.
Many Tory MPs believe that the UK has an opportunity to repatriate some powers if eurozone states seek closer fiscal integration and a treaty change.
But the foreign secretary told the BBC: "We are not at that point."
The UK has passed a law which requires a referendum to be held in the event of any major transfer of powers.
'Not on table'
A group of Conservative MPs have formed a new parliamentary group to consider ways to reshape the UK's relationship with Europe.
Some believe there is the potential for treaty negotiations shortly and want the government to be ready, so it can start to claw powers back for the UK.
But Mr Hague told BBC Radio 4's Today that a major treaty change was "not, at the moment, on the table" and the UK's priorities in Europe were to safeguard British interests and get growth going.
He said: "Don't run away with expectations that there is about to be some major treaty change, these things take years to negotiate and then to ratify in other countries.
"The moment that may come to put right some of the things we want to put right may come over a period of some years, or many years, rather than this week. Our economic priorities are absolutely top of the list this week in Manchester."
In his speech to the Conservative conference in Manchester, Mr Hague reiterated the importance of the new "referendum lock", contained in the European Union Act 2011.
"When we said that no more areas of power should go to the EU we were right," he said.
"We are just as right that the EU has more power in our national life than it should, and I believe as strongly as I ever have that when the right moments come this party should set out to reduce it."
The Conservatives' Lib Dem partners are more pro-European as a party and Mr Hague told the BBC that the desire to claw back powers was "not currently the position of our whole coalition government".
On Tuesday, the Conservative mayor of London Boris Johnson told the BBC a referendum on the UK's relationship with Europe "is not a bad idea" and said he would be "very interested" in the outcome of an "in-out referendum".
But Prime Minister David Cameron told the BBC that he did not believe a referendum on the UK's membership of the European Union was "the choice the country really wants to address", adding the EU was "vital for our trade and economic future".
He predicted there would be "a fundamental change down the track" as the eurozone countries come together to try to resolve the debt crisis but said "we mustn't get ahead of ourselves".
In his interview, Mr Hague also repeated concerns expressed by the prime minister and deputy prime minister that closer fiscal integration between eurozone countries could put the interests of non-eurozone EU states at risk.
But he said the UK was "seeking to win this argument" and was taking "pre-emptive" action on growth ahead of any eurozone changes.
In a wide-ranging conference speech, Mr Hague also criticised the decision by China and Russia to veto a UN Security Council resolution condemning Syria over its crackdown on anti-government protesters.
The European-drafted resolution had already been watered down to try to avoid the vetoes, but Moscow and Beijing said it contained no provision against outside military intervention in Syria.
Mr Hague told the conference: "The decision of Russia and China to veto this resolution and to side with a brutal regime rather than with the people of Syria is deeply mistaken and regrettable.
"We will redouble our efforts to work with other nations to increase pressure on the regime wherever we can and we assure the people of Syria they will not be forgotten."