David Cameron will make a statement to the Commons today on the phone-hacking scandal. He has some important questions to answer. Mr Cameron needs to explain why his chief of staff, Ed Llewellyn, apparently failed to pass on to him a strong warning not to take the former News of the World editor, Andy Coulson, into Downing Street. The Prime Minister also needs to say something about yesterday's allegations that his former press chief was taking informal advice from his former News of the World deputy, Neil Wallis.

Mr Cameron must also give MPs a full account of his relations with the former chief executive of News International, Rebekah Brooks. Last Friday, Downing Street revealed what it said was a comprehensive list of all the contact that had taken place between Mr Cameron and senior News International executives since the election. But only three days later it was disclosed that the list was not comprehensive at all since a social meeting between Mr Cameron and Ms Brooks had been omitted. If there is more to be disclosed about this cosy relationship, now is the time for Mr Cameron to reveal it.

We also need to hear from the Prime Minister about what was discussed at these meetings. One of them took place at Ms Brooks' home over the Christmas holiday, only days after the Business Secretary, Vince Cable, had been stripped of his responsibility for ruling on News Corp's bid to take full control of BSkyB.

The absence of support for the Prime Minister in recent days from his Cabinet colleagues has been striking. The Chancellor, George Osborne, has been as elusive as Macavity. Labour is keeping the pressure on. If charges are bought against Mr Coulson and Ms Brooks, things will get much worse. Mr Cameron's own position depends on a strong performance today.