A wealthy Russian businessman who was allegedly poisoned with sorrel soup received a threatening text message the year before he died, an inquest has heard.

Alexander Perepilichnyy, 44, collapsed and died while running near his £3 million home in Weybridge, Surrey, in November 2012.

The businessman's death was originally attributed to natural causes, but traces of a chemical that can be found in the poisonous plant Gelsemium elegans were later found in his stomach.

His widow, Tatiana Perepilichnaya, spoke for the first time at the inquest yesterday, and said that she did not know who was behind the threatening message to her husband.