Staples, the US office goods supplies company, on Tuesday offered to buy Corporate Express, a smaller Dutch rival with a significant customer base in the US, for €7.25 a share, which it said gave the group a total enterprise value of about €2.5bn ($3.7bn).

Staples said its all-cash offer was not subject to financing and wrote to Peter Ventress, chief executive of Corporate Express, to urge him to enter takeover talks.