Brown is facing Commons battle over treaty
In the early hours of yesterday morning, following an all-night session with other EU leaders in Lisbon, the Prime Minister agreed to sign up to the controversial European reform treaty.
He promised the "fullest" parliamentary debate on the treaty, but insisted it did not go as far towards European integration as the rejected constitution - so did not have to be put to a vote by the British public.
But unlike other EU leaders, he avoided toasting the agreement with champagne - perhaps because of the looming political row at home.
He insisted: "I did not drink champagne last night, or the night before, and I doubt if I will tonight either."
The summit deal extends majority voting to more than 50 extra areas of EU policy, reducing the right of one country to block deals and speeding up decision-making.
Mr Brown said he had resisted all efforts to apply new EU rules to UK policy on justice and home affairs, social security, foreign policy and defence.
In those areas, the "red lines" mean the UK can choose to opt out of joint EU deals.
"We have fought off any attempt to change the treaty in a way which would threaten the red lines," Mr Brown told a press conference in Lisbon yesterday.
He said he was confident the "fullest parliamentary debate to ratify the summit accord would demonstrate beyond doubt that he had safeguarded the British national interest".
He went on: "I believe we can make the case [in Parliament] that the British national interest has been fully defended. In the long run, for Britain and for Europe, we have agreed that there will be new priorities for the future, and we have ruled out further institutional change for years ahead."
He said the focus would be on an "agenda of globalisation" - tackling jobs, the economy and the environmental challenges facing the world. But his claim that the treaty maintained sovereignty over areas such as foreign policy and labour laws, was dismissed by MPs.
Even one of his own backbenchers, Kate Hoey, said the treaty agreed by EU leaders was virtually the same as the abandoned constitution. "If he is so pleased with this agreement and if it is so wonderful, then the people of this country should have the right to decide because it is certainly 99 per cent the same as what was agreed," she said.
David Cameron, the Conservative leader, called the refusal to seek the approval of UK voters a "denial of democracy" and accused Mr Brown of treating the public like "fools".
"We will fight for a referendum. Gordon Brown made a promise to hold a referendum on the EU Constitution. This treaty is almost exactly the same as the constitution and they have broken their promise," he said.
"We will fight for the referendum in the House of Commons and we will try to make sure he keeps his promise to the British people."
Mark Francois, the shadow Europe minister, said Mr Brown had agreed the "revised EU constitution" which would transfer massive powers from Britain to the EU. "He had absolutely no democratic mandate to do this and we will now step up our campaign to secure the referendum which he promised the British people all along."
The SNP is also set to vote with Labour MPs and Tories who oppose the lack of referendum on the treaty in the crunch Westminster vote.
The Scottish Government is angry over the enshrining of fisheries as an "exclusive EU competence".
Angus Robertson, the Westminster leader of the SNP, gave a broad hint at the party's expected action: "The SNP was the first political party in the UK to back a referendum on the original Constitutional Treaty. With the Reform Treaty being almost identical, we will decide shortly on the need for a referendum."
A source close to Alex Salmond, the First Minister said: "The likelihood is we will support a referendum but we will formally decide what to do about this at our party conference this weekend."
However the SNP has dismissed the idea of a referendum in Scotland as the high cost of staging the symbolic exercise would have to be met out of the Holyrood budget.
Despite the warnings from all sides and eurosceptic newspapers, Peter Mandelson, the European Commissioner, warn-ed Mr Brown to resist calls for a referendum. "I think the Prime Minister and the government have just got to stand their ground," he said.
Mr Brown is highly unlikely to lose the vote, however, despite mounting opposition on all sides.
Labour promised in its 2005 manifesto to hold a referendum on what was then called the constitution. But ministers defend their decision to abandon the pledge, as the document has been transformed into a series of "amending" protocols, revamping previous European treaties.
British ratification of the new reform treaty is expected to go through the Commons early next year, and Mr Brown hopes to clear all hurdles within three months.
Geoff Hoon, the chief whip, insisted he was "confident" of getting it through the Commons, Jose Socrates, the Portuguese premier and summit host, was more pragmatic.
He wished Mr Brown well, saying: "We are counting on you to sell it to the British people."
IT MUST have hurt him to say it, but Gordon Brown yesterday admitted that Tony Blair would be a "great candidate" for the new European Union president's job.
The Prime Minister was bounced into paying a glowing tribute to his predecessor after he was ambushed at a press conference.
"Tony Blair would be a great candidate for any significant international job," Mr Brown told reporters at the end of EU summit talks. "As you know, the work that he is doing in the Middle East [as a peace envoy] is something that is of huge international importance."
However, he added that it was "premature" to discuss candidates. Perhaps it was a useful diversionary device from the fact that he had practically signed Britain up to a contentious treaty and was now going back on a pledge to hold are referendum.
Mr Blair has already had his name proposed by Nicolas Sarkozy, the French President. But the appointment has to be approved unanimously by all 27 EU leaders - a difficult task indeed.
WHAT BROWN SAYS IT MEANS ... AND WHAT HIS OPPONTENENTS SAY
IT IS hundreds of pages long and full of opaque language. Add to that the differences in interpretation between French and English versions, and it is understandable how both the "antis" and "pros" can claim their arguments are right. Here we examine what Gordon Brown says against what his opponents are claiming:
SAME OR DIFFERENT FROM CONSTITUTION?
Mr Brown insists the document is an "amending treaty". He points out that its opening words say "the concept of the constitution is dead" and that the treaty would not significantly alter the legal relationship between Britain and the EU.
It is no longer a single document but a collection of legal protocols and amendments to earlier treaties. Unlike the constitution, there is no mention of the European "national" symbols of an anthem or flag.
But critics - including the Tories and the Open Europe think tank - say it is 96 per cent the same as the constitution. Even backers such as Germany and Ireland say it maintains much of the wording of the constitution.
William Hague, the shadow foreign secretary, says it remains the constitution "in all but name" and would bring "fundamental change" to member states' powers.
RED LINES: The Prime Minister says he "fought off" attempts to drop caveats maintaining Britain's sovereignty over justice, home affairs, defence, welfare and labour laws. A complex network of opt-ins, opt-outs and a veto remain, including a protocal ruling out new employment rights in Britain.
But critics say the Charter of Fundamental Rights can be cited in a UK court.
Lawyers also say cases could be taken through the British courts or possibly by someone in another EU state claiming the British protocol is anti-competitive.
FOREIGN AND DEFENCE: The government says there will be a new EU High Representative on foreign policy to implement policies initiated by member states. Governments will retain their veto over this and there is no threat to Britain's seat on the UN Security Council. There is no move to a European Defence Force.
But critics say the Foreign Minister in all but name - High Representative - would present the EU's position at Security Council meetings when there is an agreed policy.
There is a NATO-style mutual defence clause in case one of the member states is attacked.
The treaty also commits all EU members to "undertake progressively to improve their military capabilities". While this is not a single European army, it is still dictating to member states that they should invest more in their own defence forces. Critics say this unified approach could undermine NATO.
LABOUR AND SOCIAL LEGISLATION: Ministers in the UK insist Britain will retain its "competitive" approach to employment and the EU's Charter of Fundamental Rights will not change UK law, thanks to a protocol.
But opponents say that this could be challenged by the European Court of Justice and the protocol applies only to existing, rather than new, legislation.
JUSTICE: Mr Brown has promised that Britain will have the right to choose which common policies it will adopt. For example, it could have cooperation on crime and terrorism with its neighbours but would not surrender control over its borders. Critics point out that this "opt-in" protocol is not as strong as a veto.
TAX AND SOCIAL SECURITY: Mr Brown is keen to defend this one - vowing to fight against a common tax policy. He can also apply a brake to delay moves to harmonise social security.
But opponents point out that there was never any suggestion that the UK should give up sovereignty over its tax policies.
REFERENDUM: It was a promise in Labour's 2005 manifesto that there would be a vote on the constitution. The key word here is constitution. The PM insists the current amending treaty is a long way from this, and that three months of parliamentary debate offers satisfactory scrutiny.
Only a constitutionally obliged Ireland is holding a vote on the treaty.
But critics, particularly the Conservatives, are insisting that he is going back on his word as they claim the treaty is essentially the same as the constitution. They have accused Mr Brown of being scared he would lose the vote and warn the red lines can be easily breached.