Caldwells mill general manager Paul Hirst said the mill had enjoyed a successful relationship with TSO for the past 20 years.
Although he declined to reveal the annual tonnage that would be supplied to TSO, he said the deal was substantial.
The partnership deal is the first to be signed by the mill since it was bought by Klippan in a 2m-plus acquisition last October (PrintWeek, 1 November 2002).
Hirst said TSO would benefit from stabilised costs, no broker fees, and from being able to cope better with changes to pulp prices.
Keith Burbage, managing director services at TSO, said the partnership would not only help it to source paper with greater cost control, but would also enable it to cope better with surges in demand.
Caldwells mill will supply archival paper, business papers and some recycled paper products to TSO.
These include Fulmar business papers and Repeat, its recycled brand. Both ranges are produced on the mills PM5.
TSO produces official and regulatory information for the UK Government, Parliament and its Assemblies. Its clients also include the Financial Services Authority, British Telecom and the Home Office.
It is one of the UKs largest publishers by output, issuing more than 15,000 publications, CD-Roms and related products each year.
Caldwells mill has a capacity of 40,000 tonnes a year and employs 152 staff.
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