Steve Richards: Nothing reveals the tightness of Mr Brown's position more than Mrs Blair's intervention

He had pulled it off and then Cherie Blair discovered she had the power to change the agenda

Labour is staging the oddest party conference of recent times. At first it appeared to be a disciplined conference that happened to be gathering in weird circumstances. Now the conference is becoming as weird as the context in which it meets.

Labour is in a state of suspended animation. Gordon Brown is the probable next leader, but for now he is still leader in waiting. Tony Blair is going soon, but he plans to set out his own vision of the future in his leader's speech today, once more proclaiming his cautious pragmatism as radical and revolutionary.

Candidates for the deputy leadership campaign awkwardly, aware that there is no vacancy. Some cabinet ministers flirt with the idea of standing against Brown, but have no idea whether they command any significant support. Everyone plans for the post-Blair era, but Blair is still there and could be in post for almost another year.

In a political vacuum the unexpected happens. Cherie Blair's apparent outburst during Brown's speech yesterday highlights how potentially explosive this period is for the Government. Brown has spent weeks working on his "leader in waiting" speech. The wife of the "leader who is going" wipes it off the front pages.

On the fringe the Home Secretary, John Reid, suggests Labour will suffer when Blair goes. Other cabinet ministers welcome the frenzied speculation that they are ready to stand against Brown. It gives them prominence. It unnerves Brown. Although Brown delivered a good speech yesterday few will have heard it. They hear only the increasingly loud noises against him.

The advance billing of Brown's speech suggested that this was the most important address of his life. Such a billing implied wrongly that he was a free agent in a position to outline his vision for the future. But of all the prominent figures Brown is trapped most by the bizarre choreography of the moment. He walked on to the conference stage yesterday morning with thorny questions whirling around his head. His task yesterday was to address the questions that have in some cases been asked of him mischievously. That was the limit of his task yesterday, to address the questions.

How would he deal with his explosive relationship with Blair? Would he be able to say anything about his own personality in a way that sounded authentic? Would he pay homage to Blairite policies? Would he be distinctive to Blair and point to a more progressive future?

Brown answered the questions deftly enough. He pointed out that his relationship with Blair had lasted for more than two decades and a great deal of that time as PM and Chancellor. He stated that he regretted their differences over that period. This passage might have provoked the unguarded wrath of Cherie but given the circumstances Brown stepped skilfully over the landmine of his relationship with Blair.

Similarly he handled the personal side in a way that retained his authentic voice. It could have been cringe-making and over the top, as Brown attempted to follow the fashion for turning politics into a version of The Oprah Winfrey Show. Sensibly he stuck to referring to the inspiration of his parents and putting the case for politics being a more substantial vocation than a branch of show business. He had successfully negotiated two of the traps. The policy section was less fresh. It is a myth that nothing is known about Brown's future intentions. Brown's problem is the opposite. His plans are increasingly familiar and have been outlined in a series of meaty speeches over the years. Some of Brown's plans would be bold and radical, to deploy Blair's favourite adjectives. Evidently he is contemplating a written constitution and a related devolution of power. His plans to create a new board to run the NHS will elevate the debate within Labour beyond one in which only support for markets is regarded as forward looking.

But he stressed also the continuities with the Blair era, the emphasis on "reform", a conveniently vague term, highlighting a similar priority in relation to security and the same interpretation of global priorities since September 11.

Brown got through the traps. No one flinched at the personal references and with the possibly mighty exception of Cherie Blair no one fumed when Brown praised Blair. The speech was policy rich without allowing the extreme Blairites to claim that the PM was being betrayed. He had pulled it off and then Cherie Blair discovered she had the power to change the agenda.

Inadvertently she highlighted Brown's real problem in the coming months. It has nothing to do with making speeches to the party conference, nor his agenda for the future that has been forensically thought through. His problem is different. A group of people at the top of the Labour Party is out to get him.

Already David Cameron has a cascade of quotes to deploy against Brown. Charles Clarke calls Brown stupid and too cautious. Cherie Blair is alleged to have called him a liar. Alan Milburn and Steve Byers warn that Brown will move back rather than forward, whatever that means. The Conservatives do not need to invent any attacks of their own. They can rely on senior figures in the Labour Party. What is more they might be accumulating quotes for another nine months, the longest leadership contest in history.

If Brown is to succeed he must learn lessons from the wariness and, in some cases, hatred, felt by colleagues. One cabinet minister, who is supporting Brown in the leadership contest, pointed out to me perceptibly yesterday that he and his entourage must recognise that all politics is in the open now, with a 24-hour, politics-obsessed media. There is no scope for secretive manoeuvring because the media will know about it within seconds. The way politics is conducted therefore needs to be more open and collegiate.

But those that attack Brown must learn quickly too. They are doing more than enjoying a cathartic scream. They jeopardise the future prospects of the Labour government.

The dangerously weird phase can end only when Blair departs. In a strange way Blair is trapped too. He will get a rapturous reception today at the conference, but he will be listened to with a renewed reverence only once he has escaped from the current situation. Similarly it is only then that Brown will be free to speak as a leader rather than as a Chancellor with his leader sitting a few feet away from him and Mrs Blair not far behind. His big test was not yesterday, but at next year's conference if he wins the leadership contest. In the meantime there will be more unexpected explosions as Labour waits and wonders.

s.richards@independent.co.uk