Kate Day, a spokeswoman for the law firm Mishcon de Reya, said: "Proceedings were brought following defamatory articles in the US and worldwide press published over the last three weeks,"
The articles which Mr Mazzucchelli alleges are libellous appeared in two American publications, the National Enquirer and People, but Ms Day said they had been seen in Britain that was why the case would be pursued here. "Our client also lives in England," she said.
Mr Mazzuccelli, 54, an entrepreneur and international businessman, is suing his wife and Mr Trump because both parties are quoted in the articles which he alleges suggested that he was a gold digger who lied to Ivana to induce her to marry him. Ms Day said Mr Mazzucchelli would, if he won, give the unspecified damages he is seeking to charity.
Ivana, 48, a Czech-born former fashion model and Olympic skier, spilt from Mr Mazzucchelli earlier this summer. The couple were married in November 1995.
She received more than $50m (pounds 30m) in a divorce settlement from Mr Trump in 1990 after his highly publicised affair with former beauty contestant Marla Maples.
Mr Trump, 51, and Ms Maples, who married two months after their daughter was born in 1993, announced their separation in May.