Indeed, Mr Blair might find that, when it comes to pushing through laws, a departure date will help.

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Even if it goes ahead, the referendum seems not to allow for a change of the 2003 departure date.

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And the thinking among smart people at the Pentagon is that if Gates were to stay, the deal could not include any public departure date.

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Nor is securing parliamentary approval when the vote is taken in March, a couple of months before Mr Blair is expected to announce his departure date.

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Its scheduled departure date is March 25, and it will splash down in the Pacific with a payload of 2, 300 pounds of equipment and experiment samples from the Space Station.

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That will also be Mr Brennan's departure date.

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They included announcing a departure sooner than the date in late July envisaged by Mr Blair and something like a joint premiership in the interim.

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They said the e-mail stated he had told the police authority of his intention to leave for personal reasons, but he has not set a date for his departure.

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And he urged Tony Blair to set a date for his departure, to end speculation about it and ensure a smooth handover of power to Gordon Brown, the man widely expected to be the next Labour leader.

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But the date of Mr Mori's departure is still not set and, worse, none of the likely candidates to succeed him inspires much confidence.

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