Leighton Contractors and joint venture partner, Japan’s Kumagai Gumi, has fallen about a month behind schedule on its A$423M (US$330M) design and build contracts to build rail tunnel and underground stations in Perth, Western Australia.

The two contracts, which were awarded at the beginning of 2004, are part of the A$1.5BN (US$1.17BN) Perth-Mandurah railway. The delays have been caused by technical and labour problems on the NewMetroRail project.