Infrastructure Minister Ray Harmer says working out how much a road costs by averaging a number of schemes can't give an accurate figure.
He was facing questions about costs in Tynwald this week from Ramsey MHK Dr Alex Allinson, who wanted an average figure calculated form the last ten major roadworks schemes.
Mr Harmer said Island prices compare favourably to those in the UK.
But he said a variety of issues meant every road was different:
Have your say on Manx pharmacy services
Tynwald to decide on October and January half-term breaks
Sarah Astin breaks Isle of Man women’s marathon record in Seville
DOI declines to reveal charity land lease costs in Ramsey
Ballakilpheric Road shuts tomorrow
Peel Carnival needs you!
Commissioners looking for new clerk
Nobody charged for paper Manx Utilities bills, says chair