High-profile investors dropping out of the race to buy UK media company Informa – leaving the sale to just one remaining bidder – could result in a £400m (€489.6m) drop from the previously mooted £3.4bn sales price, a source close to the process has said.

Over the past month, two prominent bidders – Middle Eastern events company Dubai World Trade Centre and US buyout firm Hellman & Friedman – have walked away from any deal to buy Informa.