Carlson Wagonlit Travel (CWT) has signed a preferred supplier agreement with American Express Global Commercial Card.
Under the multi-year, CWT will promote three Amex products, Business Travel Account, Corporate Card and Corporate Meeting Card to clients in 21 countries.
Carlson said the deal would enable companies to consolidate their card programmes across countries which would assist expanse management programmes.
The deal will make enhanced data available on a local, regional and global basis.
The agreement would also support individual, lodge, and meetings and event cards.
Mike Koetting, CWT's executive vp global supplier management, said: "Many of our clients are already using American Express cards and are looking forward to the enhanced data which, when coupled with CWT Agency+Card Reporting, can provide increased visibility and understanding into travel-related expenditures."
Brendan Walsh, senior vp, American Express Global Commercial Card, Europe, said: "As their preferred payment provider, we will be able to enhance our service to mutual clients, as well as expand our relationship with new clients in many markets around the world."
Eurostar reports strong half year sales
Eurostar, the high speed rail service between London and Brussels and Paris, reported an 18.3% increase in passengers to 4.63m for the first half of 2008.
The company said sales for the six months were also up 24.7% to £368.8m.
The number of business class tickets sold in the six months rose by 8% compared with the 2007 figure.
It highlighted its faster service since its move to St Pancreas International last November, the growing cost of flying and "green" concerns as reasons for the increase.
Eurostar said it had also seen a substantial rise in passengers from outside the London region using the high speed service since it introduced through fares from more than 130 UK towns and cities.
Numbers from Derby which has a through return fare from £79 to Paris or Brussels, were up by 190% while five other cities saw a rise of more than 100%.
Richard Brown, Eurostar's ceo, said: "This impressive growth in traveller numbers clearly demonstrates that Eurostar's move to St Pancras International has opened up high-speed rail services to millions more people across the UK.
"The impact of rising oil prices on air fares, combined with growing awareness of the much greater environmental impact of flying, are causing more and more travellers to switch from plane to train.
"However, whilst we expect traveller numbers and ticket revenues to continue to rise, it is clear that the wider economic environment is deteriorating and we expect that the rate of growth will slow in the second half of the year."