A construction company lavished with government export awards is expected to plead guilty to bribing Ghanaian and Jamaican officials in the long-awaited first prosecution of a British business for overseas corruption, the Financial Times has learnt.

The case of Mabey & Johnson – which makes bridges based on the portable Bailey crossing used by Allied troops during the second world war – could become a model for future deals between investigators and corporations accused of paying backhanders to win contracts abroad.