Post Office bosses say that the Old Kent Road branch - closed for the last four weeks - will remain shut due to "unforeseen circumstances".
"We are writing to inform you that, regrettably, due to unforeseen circumstances the above branch closed temporarily on Saturday, 21 March 2020," said change manager Mohammed Islam in a letter published on the Post Office website.
"Please accept my apologies for the late notification on this occasion.
"Currently it is unclear how long this branch will remain temporarily closed.
"The Coronavirus pandemic is clearly having a big impact on all businesses countrywide and things are changing daily, however we can assure you that we will continue to work to find a solution that will restore Post Office services to the local community."
Walworth Road Post Office – which is one of the nearest alternatives to the OKR branch – is currently open just three days a week.
Elsewhere in SE1, the Westminster Bridge Road Post Office has been closed for a number of weeks, but there has not yet been any official communication regarding that branch.
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