The prime minister and chancellor have established a "working assumption" under which Gordon Brown would succeed Tony Blair midway through the next parliament, according to a report in today's Times.

Tony Blair and his associates are said to have told the chancellor that he remains the only credible successor.

Following his break in the Caribbean, the report says prime minister will revamp his Downing Street team.

Alastair Campbell, his communications chief, will not be directly replaced when he leaves later this year.

David Hill, a former Labour spinner who has been "tapped up" for a senior role, will not enjoy Campbell's power over civil servants.

Jo Gibbons, also a former Labour press officer and special adviser, is expected to take over Cherie Blair's public relations, the job currently held by Campbell's partner Fiona Millar.

The Times also reports that Tom Kelly, one of the prime minister's two official spokesmen, is still expected to be a given a more senior role despite this week's controversy over his "Walter Mitty" remark about Dr David Kelly.