Express Newspapers, owners of the Dailyand Sunday Expressand Daily Star, are offering a £1 million sterling reward for information which could help find missing 10-year-olds Holly Wells and Jessica Chapman.
It would be payable to anyone who gives information that leads directly to the arrest and conviction of anyone found responsible for the disappearance of the girls, the firm said in a statement.
The Sunand the News of the Worldnewspapers earlier announced they were putting up a joint reward of £150,000 for anyone who solves the disappearance.
Cambridgeshire Police, who are heading the hunt for the girls, are welcoming the move.
Detective Superintendent David Hankins said: "Cambridgeshire Police would like to thank the newspapers involved for their support in putting up this reward. We hope this would prompt someone to come forward with information regarding Jessica and Holly."
The school friends have been missing from their homes in Soham, Cambridgeshire, since Sunday evening. A huge police search has failed to find any trace of them.
PA