He said staff who might have come in contact with the person on Tuesday evening had been dispatched for a coronavirus test.
They will remain on leave until they receive their results.
In a Facebook post announcing the closure, the pub said “antiviral deep cleansing and antiviral misting” was underway and planned to reopen on Friday.
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The announcement said: “It was brought to our attention today that a customer who dined with us on Tuesday evening tested positive for Covid.
“As per guidelines, any staff who come in contact have been sent for testing and will remain on leave until results are obtained. ”
Contact details for customers who have registered their details for tracking and tracing will be passed to the NHS Test and Trace service, the ad confirmed.
He added: “Track and Trace have been notified and a list of customer contacts who have used the system will be forwarded to them.
“If you visited the pub on Tuesday from 8pm and did not use the Track and Trace system, please be informed.
“We are closing the pub this afternoon for an antiviral deep clean and an antiviral mist.
“We will reopen tomorrow. We are confident that we have done and will continue to do everything we can to keep you safe. ”
Customers praised the pub for its actions, with one saying it was a “responsible thing to do”.