By Ben Davies BBC News Online political staff

Stories are so widely trailed that by the time they are officially announced everybody knows pretty much what will be said.

Byers was favourite, some smart money was on John Prescott. Was Tony Blair back in town? For a long shot was it Robin Cook?

So it was with a palpable sense of excitement that journalists gathered at Number 10 on Tuesday afternoon.

We all knew which door the person making the statement was to come through - the question was who could it be?

Of course Byers was favourite, but names like Prescott and Cook were also touted.

'This is it'

When an ashen-faced Stephen Byers finally walked into that pastel coloured room upstairs in Downing Street there was an audible intake of breath.

Someone whispered "this is it" and, after many false starts, so it proved to be.

Just a few minutes earlier, the notice had come around that there would be an unscheduled briefing.

By the time reporters had run over there, checked through security and handed in their phones there were only minutes to go before the doors were locked.

Major announcement

The last time something like this had happened John Major quit the leadership of the Conservative Party when he was prime minister in a vain bid to put a stop to the in-fighting that would come to characterise his premiership.

Mr Byers made his statement at Downing Street

This time it was the transport secretary quitting his job, and acknowledging that the constant media attention was diverting attention from the "big issues" of government.

The announcement was a bit like the death of a terminally ill patient - widely predicted but in the end still something of a shock.

Mr Byers said he was leaving because it was the right thing to do both for the Labour Party and the Government.

He acknowledged that the political obituaries would be full of "spingate" rather than what he might have achieved.

And he insisted he was not a liar - although whether anyone will believe it is hard to predict.

Blair's ally

It was an assured performance but there was little doubt that it had been a traumatic few hours for Mr Byers.

Before he started talking he said he would only read the statement and he would take no questions.

When he finished he stalked from the room leaving behind him a political career in tatters.

He still has a job of course - as MP for Tyneside North.

But after five years this ultra-Blairite moderniser is no longer in the government.