Works on Castille Square are being carried out by the Grand Harbour Regeneration Corporation tomorrow, Transport Malta said.
It said the upper part of Triq Sant’ Ursula will be closed to traffic after 8.30am and will remain closed at night.
Triq San Pawl will be closed to traffic after 7.30pm and will remain closed at night.
Preparatory works will be carried out during the day but traffic will not be affected.
Motorists are advised to proceed with caution.