Geoffrey Spence, the senior civil servant appointed to run the Treasury's PFI team, will be given more resources to do the job.
Brown has strengthened his grip on PFI policy to speed up the construction of public buildings, as predicted in Building last month. This is considered crucial in the run-up to the next general election.
Supervision of PFI was under the control of the Office of Government Commerce before it was transferred to the Treasury. The OGC, a semi-detached Treasury agency, was deemed to lack the political weight to co-ordinate policy in the face of competing demands from contractors, unions and others.
The Treasury's private finance unit has been beefed up to carry out its expanded brief. Spence now heads a team of six but this is likely to increase to 11 once an internal budget review for 2003/4 is completed in the next few weeks. Several staff will be transferred from the OGC.
Spence told Building: "Issues debated about the PFI turn out to fall more into the Treasury's lap than the OGC's, such as the public sector comparator, financing and how equity works."
Spence said that he and James Sassoon, managing director of the Treasury's financial regulation and industry team, were likely to appear before Parliament's public accounts committee when it scrutinises the PFI.
A Treasury source said: "The move means that there is no longer a division of labour between the OGC and the Treasury. It is about making things easier, and speeding up the process of change to models of refinancing and standardisation.
"The unit also has a lot more contact with people like the Major Contractors Group, the PPP Forum and the CBI than the OGC unit did."
The source said putting the unit at the heart of the Treasury meant that it was in the best possible position to influence spending departments.