Barclays told CNBC it has no comment on the report. Two unnamed sources close to the bank, cited by Reuters, said there was no truth in the rumor and it wasn't exploring any potential mergers with other lenders.
Stanchart said it's "entirely focused on executing our strategy, and [does] not comment on this type of speculation."
The FT reported that one director each from the two London-headquartered banks met to discuss the possible benefits of merging. The conversation that took place was part of a wider effort by Barclays to improve its financial performance, according to the report.
Sherborne holds a more than 5 percent stake in Barclays and is one of the bank's largest shareholders.