Genetically modified crops may not remain self-contained, according to a government study published on Monday.

The report also found that after GM oilseed rape was grown, it would take 16 years before conventional crops could be grown without fear of breaching the maximum one per cent contamination threshold.

Tough new rules are to be imposed on future trials of GM crops as a result.

The Mail's front page highlights the "nightmare vision" of a countryside "polluted for generations".