Half of KFC restaurants in the UK are closed after delivery problems saw the fast-food chain run out of chicken – with the firm admitting it is ”too early to say” how long it would take to reopen its branches.

On Tuesday, KFC listed only 450 of its nearly 900 stores as being open.

Asked when customers could expect service to return to normal, a spokesperson said: “Our teams are working flat out all hours to get the rest back up and running as soon as possible – but it’s too early to say how long it will take to clear the backlog.”

Two-thirds of KFC restaurants are closed for business (Reuters/Darren Staples) (REUTERS/Darren Staples)

Signs were placed on KFC outlets around the country saying the restaurants had closed due to a shortage of the chain’s key ingredient.

KFC first apologised for the lack of fried poultry on Saturday, blaming “teething problems” with its new delivery partner, DHL.

The branches which remained open were operating with a limited menu or shortened hours.

A spokesperson said in a statement: “We anticipate the number of closures will reduce today and over the coming days as our teams work flat out all hours to clear the backlog.

“Each day more deliveries are being made, however, we expect the disruption to some restaurants to continue over the remainder of the week, meaning some will be closed and others operating with a reduced menu or shortened hours.”

The company has set up a web page where customers can check if their local branch is open.

“We’ve brought a new delivery partner onboard, but they’ve had a couple of teething problems – getting fresh chicken out to 900 restaurants across the country is pretty complex,” KFC said.

“We won’t compromise on quality, so no deliveries has meant some of our restaurants are closed, and others are operating a limited menu, or shortened hours.

“We know that this might have inconvenienced some of you over the last few days, and disappointed you when you wanted your fried chicken fix – we’re really sorry about that.”

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DHL, which recently took over the KFC contract from Bidvest Logistics, said “due to operational issues a number of deliveries in recent days have been incomplete or delayed.”