Bonhams, the London auction house, was under pressure yesterday to withdraw several pieces from a forthcoming sale of antiquities after a senior Italian politician raised questions about their provenance.

Francesco Rutelli, a former Minister for Culture, told the Italian parliament that he believed that some of the antiquities to be auctioned in London next week had been exported illegally from Italy and called for their sale to be blocked. He told reporters that he was most concerned about an Apulian vase which dates from the 4th century BC.

He said that other items in the sale “in all probability originated in Italy”, after discovering that the vase was owned by Robin Symes, the disgraced British dealer who was jailed for two years in 2005.

Symes sold looted antiquities to many Western museums, including the Getty in Los Angeles, whose former curator, Marion True, is on trial in Rome for the alleged illegal trafficking of antiquities.