Staff have been evacuated from Jennings brewery after severe flooding in the Lake District spread to the building.
Operations at the brewery, which is based by the River Cocker bewteen Keswick and Cockermouth, have been shut down with water levels inside reaching between three to four feet.
But Stephen Oliver, managing director of Marston's Beer Company which owns the Jennings brands, said there is enough beer at distribution centres across the UK to ensure pubs are not left short.
He said: "Jennings brewery is right in the heart of it. We have evacuated staff and have started to take customer calls from Wolverhampton and we will continue to do so.
"We can't brew at the moment but we have got enough beer in the system to supply customers for the time being.
"At the moment we do not know when we will be able to get in there to see to what extent the brewery is damaged."
He added that following similar floods five years ago the brewery had reopened a few days later. It is also understood much of the brewing equipment is at a level the floods have not reached.
"Customers should not see any real difference at all and we hope to have things back to normal ASAP," added Oliver.
Floods have hit the North West after severe weather led to the banks of both the Cocker and Derwent bursting.
Emergency services have rescued around 200 people from homes and businesses.
Many pubs in the area have been unable to open their doors because of the floods.
Have you been affected by the flooding? Email news@thepublican.com or call 020 7955 3714.