25 April 2012 Last updated at 05:45 ET

Article written by Nick Robinson Political editor

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The day it got really serious

 

A double dip recession. A fight to save a cabinet minister's career. The government's reputation for competence and integrity at stake. All this on a day when the Prime Minister must face the House of Commons. Few days have mattered more in the life of this government.

Be in no doubt that the economic news will trump the political in the minds of most voters. Facing the tightest squeeze to their finances seen in years, people are bound to ask "Was it all worth it?". If Labour are to persuade the electorate that there is an alternative route to growth, it is now or never. Prime Minister's Questions will not just be a test for David Cameron.

However, inside Number 10 they will be worrying more about Jeremy Hunt than the economic statistics.

Put simply, he has to prove that he was not the Minister for Murdoch but was the Minister protecting the public interest. The emails released yesterday suggest that his adviser was giving News Corp inside information and reassuring them that his boss was on their side.

Hunt's defence appears to be that his top civil service official approved of the contact. What matters then is not the contact itself but the content. Officials may, even now, be telling their minister or the prime minister that that was unacceptable. Hunt is said to believe that, though the communication with the Murdoch empire may appear embarrassingly chummy, it does not show any inappropriate impact on the process of deciding on the £8bn bid for BSkyB.

The civil service could pull the plug on Hunt or his adviser but the new Cabinet Secretary, Jeremy Heywood, is the ultimate insider and is not seen in Whitehall as that kind of official. The Speaker may condemn Hunt for releasing details in advance of a Parliamentary Statement but that would not be fatal.

I can't yet see what will force Hunt from office save a new revelation or a change of heart on his part. The prime minister wants him to stay because he knows that if Hunt goes the next in line for questions about their close relationship with the Murdochs will be him and the Chancellor, George Osborne.

What I can see is a day of huge political significance which is part of a month which may have changed this government's political fortunes for good.

Update 11.04am: My colleague Robert Peston has added one other possible peril for Hunt - a possible investigation by the Financial Services Authority into the release of market sensitive information. You can see his blog here.