Montague will join Eurostar as it prepares to switch its London base from Waterloo to St Pancras in 2007. His hire also comes as the firm's UK shareholder, London & Continental Railways, faces a bid from Sir Adrian Montague (no relation).
He will report to Eurostar commercial director Nick Mercer. His brief will centre on persuading travellers to switch from plane to train.
Montague was BBC transport correspondent from 1997 to 2004, during which time he broke the story of Railtrack's collapse. He was previously transport reporter for its Newsroom South East regional bulletin.
Montague told PRWeek that he 'admired the progress' Eurostar has made on passenger numbers and market share.
Charles, a former BBC radio presenter, joined Eurostar in 2003.