Some Belfast businesses have closed due to a lack of water on one of the busiest shopping days of the year.
A number of burst mains affected pubs and restaurants near the city hall and caused traffic chaos as emergency repair work was carried out in Cromac Street with the closure of one lane.
Colin Neill, chief executive of Hospitality Ulster, said it was an urgent situation.
He added: "This is now the most critical time of year for the hospitality sector and we need this issue resolved and the supply restored as swiftly as possible.
"The likes of pubs and restaurants in the area are booked out with Christmas customers and evening-shift staff lined up.
"We understand that these things can happen, but we need to know what the repair timescale will be so that decisions can be made in the next few hours before money is lost through customers being turned away at the door and staff having to return home after a wasted journey to work."
Mr Neill said areas like Great Victoria Street and Howard Street were reporting problems.
"We are aware of a developing situation in parts of Belfast city centre where some businesses have had their water supply cut off due to a burst main," he said.
"We have been in contact with NI Water to stress the urgency of the situation."
He later tweeted: "Some businesses now closing for the day due to bursts. Disgrace NI Water and Transport NI wouldn't give timeframe for repairs."
Many businesses survive for months on festive-season profits.
A statement from supplier NI Water said it was working to repair a number of bursts in the city centre to restore supplies to all customers.
"To enable this to happen as quickly as possible, emergency repairs need to be undertaken in Cromac Street and a lane closure will be necessary to facilitate this.
"This lane closure will result in significant disruption in and around the city centre, particularly during rush hour.
"Commuters are advised to use alternative routes and where possible to plan their journey in advance."