The route would take three years to construct.
An Bord Pleanála have further delayed their decision on a ring road around Galway City.
RTÉ are reporting that they have deferred it until October.
The route would be 18km in length, and run from Barna out towards the M6.
It's a controversial project as many homes and businesses will be impacted.
Cabinet today formally signed off on the proposed €600m ring road around Galway, with an estimated completion date of 2025 pic.twitter.com/zKmdl7utB1
— Gavan Reilly (@gavreilly) October 2, 2018
The new road will involve tunnels that go over pre-existing land in the city.
Galway Chamber CEO, Kenny Deery, said it will "decongest the city centre".
"It will give Galway the capacity to be a sustainable urban centre in the future and save hugely on journey times."
Part of the project will involve a viaduct being built over the River Corrib.
