Work is due to start on August 6 to extend the hard shoulder bus lanes along the M1 and M2 motorways.
On the M1, the existing Belfast bound bus lane will be lengthened by 4.6 kilometres between Lisburn Services (Applegreen) and Junction 7 at Sprucefield. On the M2, a new 2.2 kilometres bus lane will be provided between Junction 2 at Greencastle and Junction 1B at Duncrue.
The work, to be carried out by Graham Construction, also includes replacement of the existing bus lane signs and provision of additional CCTV.
According to a statement from the Department for Infrastructure: "The M1 and M2 approaches to Belfast are often some of the most congested sections of the strategic road network, particularly at peak times. These extended bus lanes will further improve journey times and service reliability for bus passengers without affecting general traffic flows.
"The scheme will begin by upgrading the existing bus lanes and it will be necessary to suspend their use while this work is carried out. It is anticipated however, that they will be fully operational again by the autumn. Work on the new sections of bus lanes will then continue and is planned for completion by December 2018.
"Temporary traffic management arrangements are also required to carry out the works safely and will generally consist of localised hard shoulder closures and temporary 50mph speed restrictions. Some lane closures may also be necessary at off peak times during evenings / overnight on weekdays, as well as during weekends, but these will be clearly signed in advance.
"The Department for Infrastructure has carefully planned the programme of works in order to minimise any inconvenience however, motorists should be aware that minor delays can be expected and they should allow additional time when planning journeys.
Full details of any planned traffic restrictions will be available on our TrafficwatchNI website at: http://trafficwatchni.com/home".