Motorists should avoid the Mosta Technopark roundabout area at all costs due to major road roads, Transport Malta said.
It said that the works will be completed by Saturday evening.
TM said motorists should use alternative routes through Birkirkara, Attard and Ta' Qali or through Naxxar via Iklin or San Gwann and Tal-Balal.
The authority said it is actively addressing the impact these works were having on road users by assigning enforcement officers to the area to assist in traffic direction.
It called on the co-operation of the public to avoid the area unless absolutely necessary and apologised for any inconvenience.