The chief executive of the Royal Bank of Scotland has been told to appear before MPs to answer questions on closure plans.
The Scottish Affairs Committee wants to quiz Ross McEwan on proposals to shut 62 RBS banks across Scotland and plans for a partial reprieve for 10 of these.
In a letter, committee convener Pete Wishart said the committee is "disappointed" Mr McEwan has not "meaningfully engaged" with previous requests to set a date to appear.
It adds: "Should you not respond positively to this letter the committee will have no alternative but to consider using its formal powers to summon you to appear before it."
Questions the committee wants answered include how RBS would respond to a request from the government, as a majority shareholder, to reconsider the closures.
They also want to know why RBS decided to delay the closures of some branches due to shut in May, why this did not cover other branches and how the performance of branches given a six-month extension to prove viability will be judged.
The committee also requests details of the conversations RBS had with the UK and Scottish governments after the closure decision.
The letter points out RBS personal banking executive Les Matthewson has given information but the committee believes this fails to provide the answers needed.
It continues: "These are issues that the committee wishes to explore, in person, with you, as the individual ultimately responsible for decisions made by RBS."
Mr Wishart said: "RBS is a company that is still owned by the taxpayer and we still have many questions about the decision-making process that will lead to so many communities in Scotland being left without vital banking services.
"We also want more details on the branches that have been given a reprieve - on what basis will they be judged viable in the long-term and why wasn't this opportunity afforded to all affected branches."
RBS has said the closures are in response to changes, including increased digital banking.