Mr Blair's other women

The Prime Minister's 'office wife' has just walked out on him for a lucrative post at BP. But a successor is ready and willing to take her place at the heart of No 1

The Queen is dead! Long live the Queen! In less than 24 hours Tony Blair has replaced his old friend and close adviser, Anji Hunter, with Sally Morgan, another No 10 courtier, who lost out in a battle for supremacy with Ms Hunter before the last election. As Ms Hunter heads for the private sector, she leaves behind the job in Downing Street that she ruthlessly negotiated at the expense of Ms Morgan. Rarely has the carousel turned so dizzily. Last June Ms Morgan was left with the runner's-up prize of a peerage and a job in the Cabinet Office in charge of women's issues. Now she nips back around the corner in Whitehall to take Ms Hunter's title of director of political and government relations.

The down-to-earth Lady Morgan could hardly be more different from the woman she replaces. Whereas Ms Hunter was an assiduous networker and flirtatious political schmoozer, Lady Morgan is a career Labour apparatchik who gets things done behind the scenes. When the junior courtiers in Downing Street went for a night on the town they would often be joined by Ms Hunter. Lady Morgan, a 42-year-old mother of two, preferred to head for her home in south London.

Seeking a more clearly defined job in the second term, Ms Hunter made a raid for Sally Morgan's job. Morgan mounted a fierce rearguard campaign, telling Mr Blair that Ms Hunter did not understand the party and that there would be a backlash. Mr Blair wanted Morgan to move to the job of Labour's general secretary, but she did not want to leave Downing Street. According to her friends, she was reduced to tears over the feud and what she took to be Mr Blair's ingratitude.

The irony of this sudden reversal of fortune is that all the signs pointed to Ms Hunter going upstairs to the Lords one day, while Lady Morgan was a far less likely candidate for ermine. She sits uneasily in the Lords – she was unimpressed by the bauble and found the old boys' network deeply unconvivial.

Ms Hunter, on the other hand, was an ideal courtier for Mr Blair because she was socially at ease almost anywhere. She has known him for decades, having met him at a party when she was 15 and he two years older (he fancied her friend, she later recalled, but it was Ms Hunter who became his best female mate). She started working for Mr Blair on a part-time basis after Labour's 1987 election defeat. Apart from a short break after the 1992 election, she has been working for him ever since.

Lady Morgan, by contrast, has a background more steeped in the Labour Party, where she has worked for most of her career following a brief stint as a teacher. She still has the brisk, friendly manner of a primary school teacher in one of New Labour's beacon schools and retains close ties with the unions and party activists. "She's got a fantastic mastery of detail," says one union leader. "She's also very good at using it against you."

Ms Hunter could charm and intimidate, sometimes simultaneously. Visitors to Downing Street were known to melt or blush when confronted by her tactile presence. But it was Lady Morgan, much more than Ms Hunter, who acquired the reputation of being Mr Blair's fixer and gatekeeper. Recently, though, Ms Hunter became a little demob happy. She saw it as her role to put Mr Blair's case to selected journalists. Some in the Gordon Brown camp detected the fingerprints of Ms Hunter on recent books that portrayed the Chancellor in an unflattering light. Although she remains close to Sue Nye, who works with Mr Brown, Ms Hunter was part of the Downing Street entourage that came to view the Treasury with neurotic fury. Lady Morgan – with her broader Labour Party perspective – is unlikely to become so embroiled in the rolling soap opera between Downing Street and the Treasury.

Yet Ms Hunter could be a troubleshooter as much as a troublemaker. When the former Treasury minister, Geoffrey Robinson, threatened to make hay with his memoirs, Ms Hunter was put on the case. The two of them dined together several times in the period between his departure from government and the publication of what turned out to be a relatively uncontroversial book. Whether it would have been so without Ms Hunter's intervention is not certain. There is no one left in Downing Street capable of dealing with the frayed egos of warring personalities in quite the same way. Nor is there anyone there with Ms Hunter's intuitive sympathy with floating voters. Ms Hunter liked a drink and a cigarette. Lady Morgan is a quieter character.While Ms Hunter worse svelte black and navy trouser suits, snappy, short skirts and faintly exotic make up, Lady Morgan prefers a well-cut but well-worn brown suit and sensible shoes.

But the less exuberant presence should not be mistaken for a more retiring personality. Lady Morgan can be at least as ruthless as Ms Hunter and has a similar sense of loyalty to the leader. It was Lady Morgan who argued forcefully that Ken Livingstone should be blocked from standing as Labour's candidate in the London mayoral election. Before 1997 she had the daunting task of convincing various constituencies with big Labour majorities to adopt Blairite candidates. Such a role demands a single-minded, Machiavellian focus.

Both women are in the rare position of being able to tell Mr Blair what they really think. Ms Hunter, who lives in Sussex, spoke up for Middle England. And Lady Morgan, though no less a Blairite, has been known to speak up for the Labour Party. One of her jobs was to run Mr Blair's relationship with Labour's National Executive Committee and deal with his heartfelt aversion to the party. At NEC meetings he used to pass her notes saying, "Can I go yet?" She would send one back replying, "You've only been here 10 minutes". One of the roles which will now be passed from Ms Hunter to Lady Morgan is the maintenance of good relations with potentially critical newspaper groups, especially News International. Ms Hunter was adept at keeping the Murdoch clan onside. Lady Morgan may find this diplomacy more difficult – although she does have the advantage of a savvy sister, Gill, editor of Times Saturday magazine, to tutor her in media relations.

Downing Street insiders whisper that Ms Hunter was becoming "too hot to handle" and running her own communications strategy for Mr Blair, which irked Alastair Campbell. Ms Hunter chafed openly at being considered Mr Blair's "office wife" and "gatekeeper" while Mr Campbell and Jonathan Powell ran the show. Once the dust settled, after the election, Lady Morgan (as she now was) continued to perform similar duties to those she had before the election, only with a peerage and a ministerial brief. Ms Hunter's role did not change greatly either. Restless again by the middle of the summer, she finally decided to go.

In testosterone-laden No 10 (the only other senior female figure is Fiona Millar, Cherie's aide), Mr Blair knows that he needs a woman's instincts close at hand. That is probably why he is prepared to eat the nearest thing a PM consumes to humble pie and bring Lady Morgan back to an enhanced place in the pecking order. She's much too polite to gloat.