The completion of the 17km stretch of motorway south of Dundalk last week is the latest in a series of contracts to have been won in the Republic over the past few years by the Down firm, Grahams of Dromore. The £51 million (€64.76 million) motorway contract, a joint venture with the Dublin firm Uniform Construction, involved the building of 24 road, rail, and river bridges, and was finished five months ahead of schedule.

It brings the total value of Grahams projects in the Republic to more than £75 million. They include the £9 million refurbishment of Connolly Station, the construction of three office buildings and underground car parking in central Dublin for the Department of Education, a contract which was also worth £9 million, and the construction of the new DART station at Barrow Street.

Grahams managing director Mr Michael Graham said the company had a lot of expertise in managing large-scale private and public sector projects.

"The Republic of Ireland market holds considerable potential for us," Mr Graham said. "Major construction projects on both sides of the Border are increasingly being delivered through multi-disciplined partnerships and we believe that our experience in this area has been a major factor in securing these contracts."

Set up more than 200 years ago, Grahams is one of Northern Ireland's oldest and most successful construction companies. In recent years, it has been involved in many of the region's most high-profile construction and civil engineering projects, including the M1 motorway and the Foyle Bridge.

Graham Uniform was the first cross-Border joint venture to build an Irish motorway. The project was financed by the EU Cohesion Fund (85 per cent), and the Irish National Development Plan. Project manager Mr Leo Martin said that the main challenge was the sheer scale of the enterprise.

"It involved the removal of five million tonnes of material," he said, "including 500,000 tonnes of rock, and the installation of 90 km of drainage pipes. We had to cross a number of rivers and in all we built more than 20 bridges - five of them in a 100-metre section around the Charleville interchange."

Mr Michael Graham said that the company was not deterred by the strength of sterling against the pound.

Grahams employs more than 500 people at its head offices in Dromore, and in offices in Dublin and Cambridgeshire, and has a turnover of more than £35 million sterling a year.