Further far-reaching changes in the running of 10 Downing Street are imminent. This follows Gordon Brown’s private admission that the operation set up when he became Prime Minister last June was not large and effective enough. Phase 2 of the Brown premiership is now under way, after the troubled Phase 1 during the autumn.

The word “relaunch” is never heard from Mr Brown’s advisers but that is what is happening in order to sharpen decision making and to improve the strategic planning of communications (as opposed to day-to-day press relations, which are seen as working well).

The two big appointments so far this year – of Jeremy Heywood as permanent secretary at 10 Downing Street, and of Stephen Carter, from the private sector, as chief of strategy and principal special adviser in charge of political strategy, communications and research, including the policy unit – will now be followed by the addition of more new staff.

Mr Heywood is bringing in some civil servants to strengthen the private office and domestic policy side and a number of special political advisers are being recruited. This is to provide a new viewpoint and to beef up the policy unit. In addition, new advisers on developing a media strategy are being hired. This inevitably raises questions about the creation of a prime minister’s department in substance if not in title, an issue that everyone involved wants to dodge.

As significant as these changes is Mr Brown’s acceptance that he misjudged what was necessary to run No 10. There was an unprecedented turnover of staff when Tony Blair left Downing Street last summer because virtually all the special advisers left (apart from two in the policy unit) and there were changes among most of the key Civil Service officials. The result was an initial sharp fall in the number of people working in No 10, which, visitors said, felt much less crowded than in Mr Blair’s heyday.

This was partly deliberate as Mr Brown sought publicly to distance himself from both the “sofa government” and presidential aspects of his predecessor’s style. Consequently, he brought over only a handful of officials and advisers from the Treasury to run No 10.

Mr Brown now accepts that this was not sufficient to handle an operation as complicated as a prime minister’s office. Like many of his predecessors, he has been struck by the intensity of the media pressure: when one thing goes wrong, so do two or three others.

These concerns led to the reappraisal by the Brown inner circle before and during Christmas that led to the appointments of Mr Heywood and Mr Carter. They now share an office next to the Cabinet Room, which, before last June, was used by Mr Blair as his den or private office. Mr Brown now uses a small room on the other side of the lobby outside the Cabinet Room as his private office, although he meets visitors upstairs in what is now called the Thatcher Room next to the state rooms on the first floor overlooking Horseguards Parade.

The Heywood-Carter team has reviewed the operation and concluded that it has been short of numbers, and weight, in some areas. Mr Heywood is familiar with the No 10 operation from his days as principal private secretary under Mr Blair: his rank and authority are now much greater. Mr Carter, whose main experience has been in the business and media worlds, has had to adjust to the tight and tribal world of the Brown inner circle and to the private language and understandings of politicians and advisers.

The underlying question is less what Mr Heywood and Mr Carter can do than Mr Brown’s own performance, both his willingness to be crisper in taking decisions and his public presentation. His advisers are trying to find a middle way between statements of vision (definitely out now) and his liking for long lists of detailed initiatives. They are also searching for new, more informal formats, like the successful question-and-answer session that Mr Brown undertook for the Policy Network centre-left think-tank on Friday.

The start of this Phase 2 exercise explains Mr Brown’s more self-confident mood in recent weeks and the hopes within the Brown inner circle that the worst might be over. As the polls show, however, the public have yet to be persuaded and remain very negative about Mr Brown’s performance as Prime Minister.

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