Over the weekend, Sixsmith has said that as far as he is concerned, he is still the department's head of communications, contrary to what minister Stephen Byers had told reporters. Sixsmith is reported to have said: "If you resign from your job it is probably something you would remember doing."
Sixsmith was said to have quit, along with Byers' adviser Jo Moore, over an email implying the pair had discussed burying news on the day of Princess Margaret's funeral.
Byers is sticking to his guns, saying that Sixsmith did offer to resign. Now the Conservatives are calling for Byers to step down.
The department of transport's spin machine has been in turmoil since it was revealed that Moore had sent an email out on September 11 suggesting that it would be a good day to bury bad news. She ignored calls for her resignation at the time.
Since then, it has emerged that there is serious infighting at the department, leading to the intervention of Alastair Campbell, Tony Blair's PR adviser.
Before joining the DETR, Sixsmith worked for Harriet Harman, and was the BBC's Moscow correspondent.
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