The government is not shouldering any additional costs in the construction of the Mass Rapid Transit (MRT) Line 1 project connecting Sungai Buloh-Kajang despite the depreciating ringgit.

Prime Minister Datuk Seri Najib Razak said the original value of all construction contracts, including job systems involving overseas contractors, were in ringgit, which were fixed before the local currency weaken.

"In this respect, any cost increases due to the slumping ringgit will be borne by the contractors.

"To date, the escalating costs borne by contractors amounted to RM600,000," he said in a written reply to Datuk Ahmad Fauzi Zahari (BN-Setiawangsa) at the Dewan Rakyat today.

On the progress of the MRT Line 1 project, Najib, who is also finance minister, said it was on schedule and so far, it was 70.21 percent completed.

The first phase of the project - from Sungai Buloh to Semantan - is expected to start operations on Dec 31, 2016, while the second phase - from Semantan to Kajang - is scheduled to start operations on July 31, 2017.