Caroline Spelman, the Environment Secretary, will formally pledge that the areas of woodland controlled by the Forestry Commission will not be sold off.
The decision follows public outcry over plans to sell off government-owned forests.
After a campaign led by this newspaper, Mrs Spelman performed an about-turn and said the plans would be abandoned.
The official decision was delayed until after the publication of a report by the Independent Panel on Forestry, led by the Rt Rev James Jones, the Bishop of Liverpool, which was set up last year and has received tens of thousands of submissions.
A source close to Mrs Spelman said the minister would make a statement ruling out sell-offs after the panel brings out its report this week. "We will make things abundantly clear," the source said.
In its interim report, sent to ministers last December, the panel called for schemes to encourage the plantation of more forests, which ...