The report, to be published later this year, has reportedly found that heavy mobile use is linked to brain tumours.

The survey of 12,800 people in 13 countries has been overseen by the World Health Organisation.

Preliminary results of the inquiry, which is looking at whether mobile phone exposure is linked to three types of brain tumour and a tumour of the salivary gland, have been sent to a scientific journal.

The findings are expected to put pressure on the British Government – which has insisted that mobile phones are safe – to issue stronger warnings to users.

RELATED: CONTROVERSIAL NEW BOOK CLAIMS DOGS CAUSE GLOBAL WARMING...