Ministers are planning a new law forbidding big firms to use produce from illegally deforested land.

But the firms say the law should apply to all deforestation, whether it's legal or illegal...

The firms have written a letter to the government on the closing day of its consultation on forest protection.

It says: "Restricting action to illegal deforestation would not achieve halting the loss of natural ecosystems, especially when governments have discretion to decide what is legal."

The 21 signatories include Unilever, Tesco, Lidl, Nando's, Nestle, the convenience food maker Greencore and the chicken producer Pilgrim's Pride.

Currently the government's plans refer only to major companies like these, but the signatories say this would allow medium-sized firms to continue importing large amounts of commodities from previously forested land.

They are pressing for a level playing field so smaller operators don't gain a competitive advantage...

A government spokesperson [...] said tackling illegal forest-felling was the obvious place to start...

Although some environmentalists have supported the letter to government, other say the proposed targets are inadequate...