The outer circular highway connects to an expressway to the South of the island and the High Level Road, a key trunk route leading out of the capital Colombo at Kottawa.
It also connects to a new expressway to the international airport at Kerawalapitiya and a planned expressway to Kandy at Kadawatha.
There will also be an interchange at Kaduwela.
"In addition it was decided to build an interchange at Athurugiriya because the area is fast developing." Pemasiri said.
The first 11 kilometre section of the 29.1 kilometre highway from Kottawa to Kaduwela is expected to be completed by May 2013.
The 8.9 kilometre section between Kaduwela to Kadawatha was started in January, 2012 and is expected to completed by January 2015.The contract negotiations for the third section are underway, an update on RDA's website said.