Mediator, a drug licensed for use by diabetics that became widely prescribed in France as a slimming aid, "probably" caused at least 1,300 deaths before it was withdrawn, a study published on Thursday said.

Mahmoud Zureik of the National Institute of Health and Medical Research (Inserm), who co-led the probe, told AFP that around 3,100 people had required hospitalisation during the 33 years during which the drug was sold.

However, these figures could well be an "underestimate," he said.