The race is the subject of intense speculation as the anniversary of last year’s civil uprising approaches on Feb 14.
The 2011 Bahrain Grand Prix was initially postponed and then cancelled altogether in the wake of the violence which claimed at least 34 lives.
The letter coincides with a report in the Gulf Daily News that a 51 year-old Briton, Peter Morrissey, had two fingers cut off by sword-wielding robbers in Karranah, which is near Manama.
The authorities in Bahrain are trying to stem a tide of negative publicity and have called for calm, insisting that reports of unrest have been exaggerated and in some cases, twisted.
The Inspector-General of the Ministry of Interior issued a report this week into allegations made by Mr Nabeel Rajab, President of the Bahrain Center for Human Rights, that he was attacked an beaten up by police officers.
