KFC said the issues were down to "teething problems" with a new delivery partner.
DHL won the KFC delivery contract a few months ago, which we reported on here.
In a Facebook post, the company said, "Some chickens have now crossed the road, the rest are waiting at the pelican crossing. But the good news is we've now set up a page on our website - www.kfc.co.uk/crossed-the-road - so you can check where your nearest open restaurant is."
KFC said its teams are working round the clock to get the rest back up and running as soon as possible.
They added, "We won't compromise on quality, so no deliveries has meant some of our restaurants are closed, others are operating a limited menu or shortened hours."
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