Barclays has been exploring a potential merger with rival banks including Standard Chartered, according to a report in the Financial Times.

The FT said Barclays directors had held “exploratory conversations” about possible deals in response to pressure from Edward Bramson’s US-based activist investment fund Sherborne, which has a 5.4% stake in the bank.

John McFarlane, Barclays’ chairman, was in favour of a deal with Standard Chartered, according to the FT, while Sir Gerry Grimstone, who chairs the Barclays International unit, was also said to be supportive of the idea.

A private conversation took place between a director at each bank about the potential benefits of such a deal but no formal or informal bid approach had taken place, the FT said.

Barclays declined to comment on the report.

A spokesman for Standard Chartered said: “We are entirely focused on executing our strategy and do not comment on this type of speculation.”

Shares in Barclays were down 0.4% on Wednesday morning after the report was published, while Standard Chartered shares rose 2.2%.

Sources close to Barclays poured cold water on the report and said the bank was not working on a deal with any of its rivals.

Bramson is calling for a shake-up of the bank that is thought to involve a radical reduction in activities at its underperforming investment bank, in a plan to cut costs and boost shareholder returns.

Jes Staley, the chief executive of Barclays, met Bramson in New York earlier this month and was told by the activist investor that he was still working on his proposals for the bank’s future.

Also this month, Staley was fined £642,430 by UK regulators for a breach of conduct after he attempted to unmask a whistleblower. As well as being fined by the Financial Conduct Authority and the Prudential Regulation Authority, Barclays said it would claw back £500,000 of Staley’s bonus over the matter.

The bank will also have to report annually to the regulators detailing how it handles whistleblowing after they expressed concerns about its existing systems.