Traffic congestion could strangle the potential for development at the Maze, it has been claimed.
DUP MLA Jonathan Craig said that roads to the M1 motorway - which links Belfast to Dublin and western parts of the province - must be urgently upgraded.
During a debate in the Assembly, he said motorists would tolerate delays for the first couple of years but a more permanent solution must be found for the longer term.
"Traffic congestion and inevitable delays will strangle the potential of the site," the Lagan Valley MLA said.
"If the site is to develop its full potential it is clear that the road links which directly link on to the M1 are required."
The Office of First and Deputy First Ministers has allocated £30 million to improve road infrastructure around the Maze.
This will include a bridge over the M1 to facilitate traffic coming from the west as well as a new dual carriageway towards Sprucefield.
However, Mr Craig also called for a further investment to develop the nearby Knockmore Link.
He added: "That would open not only development of the Maze but the Knockmore Industrial Estate which has waited patiently for 20 years."
The Royal Ulster Agricultural Society moved its headquarters from the Kings Hall in south Belfast to a 65-acre site at the Maze last year. They are currently building an arena and equestrian centre of excellence and will host the annual Balmoral Show in May bringing thousands of cars on to the rural roads.