The junction of Deepdale Road, Ribbleton Lane and Church Street is closed.
Preston Bus tweeted about the gas works diversion on Friday 5 November.
Read more: Preston Bus diversions as junction of Deepdale Road, Ribbleton Lane and Church Street closed
A spokesman for gas network Cadent said: “We located a leak on a gas main that required urgent attention.
“Our teams worked on this over the weekend and we expect, hopefully by tomorrow, to have the road fully open again.
“We appreciate everyone’s patience and understanding. No-one lost supply as a result of this incident.”
Cadent are on track to complete the work before or on 12 November.
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